Max Muncy hit a tying infield single and Betts singled home the winning run with two outs, helping the Dodgers edge the Arizona Diamondbacks 3-2 on Thursday for their major league-leading 45th comeback victory.
"I think that may be one of my first pinch hits, so that part was pretty cool," Betts said. "I was hoping not to hit, but you get to a point where the situation calls and you turn your brain on and you're ready to go."
The Dodgers didn't take the lead until Arizona starter Zac Gallen left after eight innings. He struck out a career-high 13.
Gallen retired the first 11 batters he faced, striking out five in a row. He struck out the side in the eighth. The right-hander allowed one run and two hits in a career-best eight innings.
"He was just in complete control, domination," Dodgers manager Dave Roberts said. "He's fun to watch. I'm glad we don't see him again this year."
Craig Kimbrel (6-6) got the win despite again struggling in the ninth.
"The stuff is startling to slide a little bit, the fastball velocity," Roberts said. "I've just got to continue to look at this. We've got to have our best guys at the back end."
Christian Walker slammed a 435-foot shot into the left-center field pavilion - his 36th homer overall and sixth against the Dodgers this season - for a 2-1 lead against Kimbrel.
"He was ahead of Bellinger 0-2 and then it ended up being a 3-2 pitch kind of down in the bottom of the zone, right in his honey hole," D-backs manager Torey Lovullo said. "We just couldn't make some pitches in a key situation to Bellinger. It's tough to navigate through that, especially the guys who were coming up behind him."
After Trea Turner grounded out to third, Freddie Freeman was intentionally walked. Will Smith loaded the bases on an infield single that diving shortstop Geraldo Perdomo kept from reaching the outfield.
"Belli did a great job getting on second base leading off, then we got a little momentum," Smith said.
Joe Mantiply came in to face Muncy, who hit a slow roller to third that scored Bellinger for a 2-all tie.
Dodgers starter Julio Urías gave up one run and three hits in 5 1/3 innings. The left-hander struck out five and walked one.
Gallen gave up a pair of two-out hits - a triple by Smith and an RBI double by Muncy - that allowed the Dodgers to tie it 1-all in the fourth.
"He was making pitches and keeping us off balance and kind of stalled us for a little bit," Smith said.
The D-backs led 1-0 on Stone Garrett's sacrifice fly in the third. Sergio Alcántara singled and Daulton Varsho followed by grounding into a fielder's choice. Second baseman Gavin Lux's throwing error allowed Alcántara to take third, and Varsho moved up to second. Three batters later, Alcántara scored.
In the ninth, the Dodgers challenged Kimbrel hitting pinch-hitter Jake McCarthy with a pitch leading off. After a review, crew chief James Hoye announced the call stood.
McCarthy thought he'd stolen second to put the go-ahead run in scoring position, but another replay review overturned the safe call. Walker then came to the plate and put the D-backs ahead on a 2-2 pitch from Kimbrel.
Dodgers: All-Star RHP Tony Gonsolin (forearm) threw to hitters in an up-and-down bullpen using his entire pitch mix. "The stuff looked good," Roberts said. "My eyes were telling me it was a really good effort." The 16-game winner will throw another bullpen in a couple of days. ... RHP Blake Treinen (shoulder) won't throw again until Saturday and see how he responds. "He's frustrated. He's not bouncing back," Roberts said. ... RHP Brusdar Graterol (elbow) was activated off the IL. ... LHP David Price (wrist) threw a simulated inning to hitters. "He looked good. He was letting it go," Roberts said.
Turner went 0 for 4, including two strikeouts, to snap his 18-game hitting streak.
Turner also had another streak end. He had reached base safely in each of his last 47 games against the D-backs, the longest current streak for any active batter against any team.
Diamondbacks: Hadn't announced a starter for Friday's opener of a three-game series against San Francisco.