Jansen struck out Wil Myers and rookie Jake Cronenworth - both of whom hit grand slams this year - to save the 3-1 win for Gonsolin on Tuesday night. The Dodgers snapped the Padres' eight-game winning streak and regained a 2 1/2-game lead in the NL West.
Jansen earned his 11th save in 13 chances.
''I was very proud of him,'' manager Dave Roberts said. ''I actually thought he threw the ball well. Big punchout to Myers and Cronenworth, so I really feel good about his outing.''
The seven-time NL West champion Dodgers, being pushed by a Padres team that hasn't been to the playoffs since winning the division in 2006, bounced back from a 7-2 loss in the opener of the series between the NL's two best teams.
The Padres, cruising toward a berth in the expanded playoffs, lost for just the third time in 15 games.
Reigning NL MVP Cody Bellinger also had an RBI single, in the third, and Rios made it 3-1 when he homered deep into the seats in right leading off the fifth, his fourth.
Gonsolin (1-1) held the Padres to one run and four hits, struck out two and walked none in his longest outing so far.
The 26-year-old rookie kept the Padres off balance except for the third, when they manufactured one run. Jurickson Profar hit a leadoff double over right fielder Mookie Betts, advanced on Greg Garcia's sacrifice and scored when Trent Grisham beat out a bunt for a single.
After Grisham's single, Gonsolin retired 14 of the next 15 batters.
''We've seen some good ones from Tony. For him to go seven was really remarkable,'' Roberts said. ''He worked ahead all night long. He was in control, which was really good to see.''
Gonsolin said he didn't feel any pressure after the loss Monday night.
''Every game I go out there it's the biggest game for me,'' he said. ''I just want to go out there and throw strikes.''
Gonsolin ''has been tough on the entire league this year,'' Padres manager Jayce Tingler said. ''That's the second time we've seen him this season. We actually saw him four or five innings in spring training. He's good. He's been a tough matchup for us. I thought his velo even picked up later in the game.''
Davies, who also lost to the Dodgers on Aug. 12, allowed three runs and eight hits in six innings, struck out five and walked one.
Dodgers: Activated Turner from the 10-day injured list. He missed 13 games with a left hamstring strain. Before going on the IL, Turner was batting .282 with two homers and 20 RBIs in 32 games during the shortened season. He started at DH. In a corresponding roster move, the Dodgers optioned RHP Josh Sborz. ... Reliever Caleb Ferguson left after feeling something in his left elbow after facing just one batter in the eighth. Roberts said Ferguson will get an MRI on Wednesday in LA.
Dodgers: RHP Dustin May (1-1, 2.81 ERA) is scheduled to start the series finale Wednesday afternoon. Both of his decisions came against San Diego.
Padres: LHP Adrian Morejon (2-0, 2.53) is set to go for the Padres.
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