Muncy hit a two-run homer in the seventh against Mark Leiter Jr. and a solo drive in the ninth off Brad Boxberger, tying the New York Mets' Pete Alonso for the major league lead with 10 home runs. Muncy has homered nine times in the last 12 games.
"Every guy is important, but Max is always in the middle of things, so when he is going well it seems like we put up good numbers," Dodgers manager Dave Roberts said.
Outman was 4 for 5 with four RBI, hitting a solo shot in the second off Hayden Wesneski (1-1) and a two-run homer in the ninth against Boxberger. Outman leads rookies with a .314 batting average, seven homers and 19 RBI and 1.121 OPS..
"James has carried us a lot. He's gotten some big hits obviously. It's just an opportunity that presented itself essentially the last couple of days of spring training and he's taken advantage of it, earning more opportunities," Roberts said.
Los Angeles rebounded from a 13-0 loss Friday.
Nico Hoerner hit a two-run homer for the Cubs, who lost just for the second time in seven games. Hoerner has homered in consecutive games.
One day after Drew Smyly took a perfect game into the eighth inning, Wesneski faced a no-out bases-loaded jam in the first inning. Mookie Betts singled, Freddie Freeman doubled and Muncy walked as the Dodgers matched the number of base unners they had Friday.
Dodgers starter Dustin May found himself in the same predicament as Wesneski in the first inning with bases loaded and no outs. Hoerner, who led off with a single, came around to score on Seiya Suzuki's fielder's choice. May ended the first inning by getting Cody Bellinger looking and Patrick Wisdom to pop out.
May (2-1) settled down after a rocky first to pitch 5 1/3 innings. He allowed two runs and two hits with six strikeouts and pitched around three walks.
Outman led off the second inning with a home run into the right-field basket.
"The more reps you get, the more comfortable you feel for sure," Outman said. "I don't know why it is but I think it is the clubhouse, the guys are great, so that's obviously it."
Martinez doubled and scored on Outman's single in the fourth ifor a 3-1 lead.
"He's smart and he is always talking about what pitchers are doing," Muncy said. "For a guy that doesn't have a lot of experience with a lot of these pitchers, it's really impressive for him to be so open to what we talked to him about."
Eric Hosmer hit an RBI double in the fourth.
Wesneski (1-1) lasted 4 1/3 innings and gave up three runs on five hits.
Muncy's recent offensive surge has been a team effort. Roberts credits Muncy and the hitting staff for making the proper adjustments in the batter box. "I give him and a lot of the hitting guys a lot of credit, kind of detecting something and making a change, and obviously Max is got to buy into it. Once he sort of did that step-back move it's been a different season for him. It's something he's committed to and obviously, it's nice when you get results. He's just taking really good at-bats."
Dodgers C Will Smith is not expected to return to the lineup through the end of the trip, which ends Thursday in Pittsburgh. He's missed nine straight games with a concussion. "We're obviously being very cautious," Roberts said. "There is going to be a ramp-up (in testing). Until he does that and passes those tests he's not going to be in a Major League game."
Cubs RHP Kyle Hendricks (right shoulder strain) was scheduled to pitch three innings in an extended spring training game and RHP Codi Heuer (Tommy John recovery) was also scheduled to throw one inning of a simulated game Saturday game.
DAY AND NIGHT
The Dodgers are 1-5 in day games. Last season, they were 31-14.
Los Angeles recalled LHP Victor González from Triple-A Oklahoma City and designated Jake Reed for assignment, a day after he allowed six runs and five hits while getting two outs in his season debut. González was 1-0 with 1.29 ERA in six games for Oklahoma City.