Wait ... Matt Kemp is a star again?

In his book, "Whatever Happened to the Hall of Fame?" in 1995, Bill James gave us the Keltner List -- 15 questions meant to aid the thought process while evaluating the Hall of Fame worthiness of a player. The first question, and perhaps the most well known, is, "Was he ever regarded as the best player in baseball? Did anybody, while he was active, ever suggest that he was the best player in baseball?"

That is a high bar, one that few players can clear, which is precisely why it leads a list of inquiries meant to clarify whether someone belongs in Cooperstown. There are few players active at any given time of whom it can be said. Of those active today, I would argue that there are but two -- Albert Pujols, who took the baton from Barry Bonds in 2007, and Mike Trout, who picked it up and has held it all to himself pretty much since the latter stages of his rookie season.

In between, though, for a very brief time, there might have been an intruder to the conversation: Matt Kemp.

The best way to address the best-of topic is from a multiyear perspective, which is why Trout is so tough to knock out. You have single-season explosions that briefly make you believe a player is emerging as a best-in-the-game candidate, only to rediscover that it's consistent greatness, not fleeting greatness, that marks those who can claim this title. This is where Bryce Harper's 2015 season (10.0 WAR) currently resides.

As for Kemp, if you have no recollection of that time when that answer might have been him, don't worry. It was a long time ago and if it was ever true at all, it wasn't for very long. This dates to Kemp's career season of 2011, so it fits into the crevice between when Pujols' skills first started to erode, and when Trout's first began to become apparent. That happened to be when Kemp was at his best. That season, he hit .324/.399/.586 with 39 homers, 126 RBIs, 40 stolen bases and 115 runs. His average ranked third in the NL, 13 points behind league leader Jose Reyes.

Thirteen points. Thirty-nine homers. That's how close Kemp came to winning the Triple Crown and becoming the fifth player to post a 40-40 campaign in the same season. Oh, and Kemp won the NL Gold Glove that year for his work in center field, where he started 159 games for the Dodgers. He led all NL position players in WAR but finished second to Milwaukee's Ryan Braun in the MVP voting.

That's when Matt Kemp was at his best -- as good as anyone. He was rewarded for it, too, by the old Dodgers regime when Frank McCourt still owned the team. After that season, L.A. signed Kemp to an eight-year, $160 million deal that, according to Cot's Contracts, was at the time the richest pact given to a National League player. It's the contract he's still playing under, all these years later.

The contract put Kemp at the pinnacle of his sport. At the time, he could not know there was no place to go but down from there.

On the Depth Charts tab in MLBPET (my projection and tracking system), each player's WAR total, prorated to 162 games, is listed beside his projection. That way, at a glance, you can see where reality has veered away from expectation. There are 1,084 players currently listed on those depth charts. Only 42 of them are on pace to outperform their forecast by more than Kemp, who through Monday was on pace for 3.6 WAR, though he was forecast for just 1.0. Last season, he was below replacement at both Baseball Reference and Fangraphs.

Only two of those 42 are older than Kemp: Atlanta's Nick Markakis and Houston's Justin Verlander. This is just not the kind of breakout you can see coming. By any measure, Kemp's late-career explosion has been a shocker. And there is no way the Dodgers thought that when they reacquired Kemp over the winter, that it would be this Matt Kemp who showed up.

"I had him penciled in impacting our clubhouse in a positive way, with professionalism and preparedness," Dodgers manager Dave Roberts said. "Outside of that, I just didn't know what to expect, to be honest with you. You look at his track record, he's been a successful offensive player for many years. So that's kind of what we were betting on."

Last winter, when Kemp was acquired from Atlanta for Charlie Culberson, Adrian Gonzalez, Scott Kazmir, Brandon McCarthy and $4.5 million, his addition to the Dodgers' roster was assumed to be an on-paper move only. It looked like an NBA-style trade, where the money involved in a transaction meant more than the names and talents of the players involved. The Dodgers were open to the notion that the move was made to help get L.A. under this year's luxury tax threshold and, throughout the industry, the assumption was that the Dodgers would try to flip Kemp, since their roster seemed full. At the very least, it seemed as if the Dodgers would buy him out.

It's not as if the current Dodgers front office was attached to Kemp. One of the early moves of the Farhan Zaidi-Andrew Friedman braintrust was to ship Kemp to the San Diego Padres in a deal that brought back catcher Yasmani Grandal. This time, instead of pushing for a buyout, when unsurprisingly no taker emerged for Kemp's contract, the Dodgers offered Kemp a chance.

"We were candid with Matt that we made the trade for financial reasons," Zaidi, the team's general manager, told me during spring training. "But what he told us was that all he wanted was an opportunity. He loved being with the Dodgers before and he just wanted a chance to earn a spot on the team and earn playing time."

Kemp took the offer seriously and, to their credit, the Dodgers gave him a bonafide chance at playing time during spring training. It didn't hurt that he showed up 40 pounds lighter than he was last season in Atlanta, where after a fast start he battled hamstring issues, the latest in a string of injuries that gnawed away at his former MVP-level play.

It's a cliché to make fun of that thing in spring training, when players show up and declare themselves to be in the best shape of their lives. For one thing, even when it's true -- and Kemp was so much leaner when he arrived at Camelback Ranch that it was eye-popping -- being in better shape doesn't necessarily translate to better production. It doesn't hurt, but the problem is, often when a player makes such a concentrated effort to reform his nutrition and workout habits, it's because his skills are on the wane. It's a matter of desperation. At 33, it seemed likely that would be the case for Kemp.

"I was motivated no matter what the situation was, wherever I had landed," Kemp said. "But of course I wanted to stay with the Dodgers when I found out I got traded again. But you never knew what was going to happen. Just worked out, got ready. I knew I had to come into spring training and show them what I could do. I felt like I did that and they liked what they saw, so they kept me on the team."

Then again, these are the Dodgers, who have been as good as any organization in baseball when it comes to taking other teams' lemons and turning them into sweet lemonade. Kemp isn't even the best example of that on this year's roster. That would be infielder Max Muncy who, before this season, had a career average of .195 with five home runs. This year, he has put up a .987 OPS, 15 homers and a WAR pace of 4.6. Tell me you saw that one coming.

The point is: The part of Kemp's return that we were all overlooking was if there was one team's culture and processes that could revive his career, it was probably that of the Dodgers.

"That goes to scouting and the front office, finding guys on the come," Roberts said. "[Chris] Taylor last year did it for us, and you mentioned Muncy this year, guys getting opportunities. But I also think that it's an environment. One where guys come in here, including young players like Cody Bellinger last year, come in and feel comfortable and have an opportunity to flourish. That speaks to the guys in the clubhouse and the coaches."

But let's not give the L.A. machine all of the credit. According to the Sprint Speed metric at baseballsavant.com, Kemp's rate of feet-per-second has increased from 24.9 last season to 26.6 this season. Among 396 players with at least 10 measured events in both seasons, Kansas City's Mike Moustakas is the only other player to have seen an increase that large. When asked what he did this winter to accomplish that, Kemp just shrugged.

"Just got leaner and worked hard," Kemp said. "Came into spring training feeling great. That's pretty much it, nothing else to it."

The spring in Kemp's step was apparent from Opening Day, when he received a robust welcome at Dodger Stadium upon being introduced with his new and old teammates, most of which comprised last year's National League champions. Afterward, when asked if he felt like a rookie again, Kemp said, "Definitely don't feel like a rookie. But I feel like a kid. Not a rookie, but an old kid."

The combination of elite play and the big contract put the critical target on Kemp's back, though it arguably had been there all along. As far back as 2010, former Dodgers GM Ned Colletti had some interesting critiques about Kemp's defense and baserunning. During his first L.A. stint, he fell into the celebrity culture that can swallow a young athlete, and that didn't help matters. Kemp himself wrote when he left San Diego that he had not been all he could be.

Questions about Kemp's effort level, whether it was on-field action or his general physical condition, seemed to rise every season. According to FanGraphs, from 2010 through last season, Kemp's minus-66 defensive runs saved was the fifth-worst total in baseball. That's the type of thing that attracts notice when you're slated to earn $160 million. Thus Kemp's name became an obvious choice for anyone compiling a list of baseball's worst contracts.

Yet what this season has done, more than any other, is to raise a key question about Kemp's hit-and-miss past few seasons. Have the shoddy defense and the perception of poor conditioning actually been a product of his injuries?

That's the kind of question that is probably impossible to truly answer, but consider that back in 2014, when the Dodgers first arranged the deal that shipped Kemp to San Diego, the trade was initially held upbecause it was discovered that Kemp has two arthritic hips. That seems like a problematic condition for anyone whose job description calls for quick bursts of running. And it's far from the only physical issue Kemp has dealt with over the years.

"I think if you talk to Matt, he'll say that it's a different team and a different vibe than when he was here before," Zaidi said. "He's obviously been with a couple of different teams, different organizations, and experienced different things at those stops. For somebody who's as accomplished as he is, who has done a lot of things in the game, having stability and being a part of a contending team are the most important things. His journey over the last few years has brought that to the fore for him. And he's playing and acting, not just talking the talk but walking the walk. That's been a great development for us."

The injury problems might help explain the inconsistent nature of Kemp's post-2011 seasons. An aggressive hitter, Kemp was already predisposed for a certain amount of streakiness. But often, it has been as if he turns into a different player from half to half, or even month to month. Here's a roundup, based on Kemp's game logs from Baseball Reference, and his comments in each Baseball Prospectus annual:

• In 2012, Kemp had a 1.163 OPS for roughly two months, then injured his hamstring. After missing the better part of two months, he ended up posting a .792 OPS over his last 70 games and tore a labrum in his shoulder after running into an outfield wall.
• In 2013, after having surgery on that shoulder, he started the season with a .666 OPS during the first half. Over the second half, he rebounded with a 1.047 mark -- but that was over just 12 games. That season, he had more hamstring trouble and hurt his ankle, which required more surgery after the season.
• In 2014, Kemp played a full season. He had a .760 OPS in the first half and a .971 after it. Whether that was related to the aforementioned surgery, that's hard to say, but because the first-half shortfall was largely due to a lack of power, it seems logical.
• In 2015, his first in San Diego, Kemp had a .674 OPS in the first half and an .868 OPS after the All-Star break.
• In 2016, Kemp was at it again while splitting his season between San Diego and Atlanta. He had a .723 OPS in the first half, and a .906 OPS in the second.
• Last season, despite a career pattern that seemed to have become ingrained, Kemp flipped the script, though that might well be a product of the hamstring issues that led to so much trouble as last season progressed. Through June 2, Kemp had a 1.001 OPS for the Braves. From then on, it was .634.

The rough finish to last season largely colored the perception of Kemp headed into the winter, and was why when the Dodgers landed him, no one took the baseball part of it all that seriously. (The notable exceptions to that being the Dodgers and Kemp.) This season, Kemp's OPS had reached .953 before a recent downtick, and he was leading the NL with a .338 batting average. His career patterns make a current 2-for-25 slump a concern, but it's too early to be alarmed by it. After all, Kemp has remained in the lineup pretty much every day -- he's still healthy -- and one of his two hits was a grand slam in New York over the weekend.

When asked what it is about the Dodgers that leads to so many of these kinds of out-of-nowhere stories, Kemp said it's less about analytics or technical tweaks, and more about attitude.

"It's the culture of the clubhouse, knowing guys and getting to know guys," Kemp said. "I don't think they'd be willing to bring in anybody that didn't want to be part of the culture or what we want to succeed by. That's a winning culture and winning attitude. It's all about playing together. We've had a lot of injuries so far, but we've had guys who've that have stepped up and put us in position to be successful."

Still, for Kemp's happy redemption story to play out, he's going to have to do something he hasn't done since that magical 2011 performance: Put two big halves of baseball together.

Kemp's performance would have been welcome news for the Dodgers in any context. But it has been especially timely given the rash of injuries that L.A. has battled. Corey Seager is out for the year, Justin Turner didn't debut until mid-May because of a fractured bone in his wrist. Clayton Kershaw and most of the rest of the Dodgers' rotation has been on the shelf at various times. Even consistent-as-the-setting-sun closer Kenley Jansen struggled out of the gate when his spring routine was halted by a balky hamstring.

As it was, the Dodgers stumbled to a 16-26 beginning and with key performers falling left and right, things looked bleak for a time. Since then, L.A. has gone 26-10. During that period, Kemp led the team with a .327 average, 37 hits and 30 RBIs. If you hadn't seen the ups and downs Kemp experienced during his years in San Diego and Atlanta, you might not have noticed that any time at all had passed since his first L.A. tenure. But it's a different team, from the front office to the clubhouse to the manager's office. It's a different Kemp, too, one who has fit perfectly into the established Dodger clubhouse dynamic. That he would be was apparent all the way back in spring.

"He would never say this himself, but he has a lot of history and a lot of relationships here that go beyond the fact that he's played with some of these guys before," Zaidi said back in March. "I was talking to one of our clubhouse guys early in camp, and he was mentioning how Matt took him and a bunch of the other clubhouse guys out to dinner the night before. One, that's just a generous thing for any player to do, but also it speaks to the fact that he has a relationship with these guys and there is a lot of mutual respect."

Assuming that health doesn't again torpedo Kemp's efforts at putting together a full season, there's no obvious reason why he should drop off. Sure, his BABIP (.360) is high but when Kemp has been at his best, this is what he does. His BABIP has exceeded .350 five times and reached as high as .411 (way back in 2007). Even if Kemp's BABIP regresses toward his career mark of .339, his numbers should remain productive. And those numbers, if they continue, will be contributing to a push for the postseason, where Kemp has not been since 2014, his final season in L.A. before the trade to San Diego.

"We're playing really good right now," Kemp said. "That's all we're worried about. We're going to get guys back and it's just going to make our team better when we have our full squad. The young guys who have stepped up, that kept us in it and now we're starting to roll. I think we're pretty excited about that. We're playing some good baseball right now."

One of the biggest changes for Kemp this season has been an enhanced launch angle, which might be that Dodgers' improvement system at work once again. More than anything though, he has simply hit the ball harder, more often. According to Fangraphs' version of well-hit percentage, Kemp's 43.7 percent rate is easily a career high. According to Statcast, his wOBA (.376) is actually a little low in relation to the quality of the balls he has struck: Kemp's expected wOBA is a rousing .399.

"It's work," Kemp said. "Working in the cage. We've got really great hitting guys who are always trying to find ways to get better as a team. All of us. We're always talking about hitting and figuring out ways to get even better than we are."

Everything -- the leaner build, the first-half results, the underlying metrics -- point to this being a true bounceback for Kemp, seven years after his epic 2011 season. This is the seventh season of that eight-year deal. With so much money having already poured into Kemp's bank account, if he had shrugged off his injuries and faded into part-time status while playing out the string, it probably wouldn't have created much of a ripple on the storytelling front.

That Kemp refused to accept the passive outcome is what makes his 2018 narrative so compelling. That's especially so because as much as Kemp needed the Dodgers, as it turns out, they needed Kemp -- this version of Kemp -- almost as much. In doing so, the Matt Kemp story has taken a turn few would have predicted. The old kid might not be quite at his peak, MVP level, but he is at least doing a pretty good imitation of that player.

"The impetus to making the trade wasn't necessarily about a baseball trade," Zaidi said. "But it's exciting to think that it may actually wind up making us a better team in the process."