SAN DIEGO -- It was all starting to look a lot like last October for the Dodgers.

The defense was letting down a pitching staff that threw up a lot of zeroes against one of the best lineups in baseball. The Dodgers’ offense was leaving runners on base at an alarming clip. The Padres, on the other hand, were playing like the more confident team.

But that all changed with one swing from a superstar.

With Los Angeles down to its last out, Mookie Betts rose to the occasion, smacking a game-tying homer off Padres All-Star closer Josh Hader. In the 10th, rookies Michael Busch and James Outman delivered to help the Dodgers secure the first series between the two division rivals with a 5-2 win on Sunday at Petco Park.

“He’s the best player on the field,” Dodgers manager Dave Roberts said of Betts. “He’s always got to believe that, and the great thing about this game is the players win the game. Today, [Betts] had an opportunity and he clutched up for us.”

After a hot start to May, Betts had a tough weekend at the plate. But his ability to change a game with one swing of the bat is what makes him one of the best players in baseball. And when his team needed him most, Betts was able to turn on a 3-1 Hader fastball and send it into the seats.

It served as a gut punch to the sold-out Petco Park crowd, and it set the stage for the Dodgers’ young players to get to work in the 10th. That’s when Busch, who hadn’t taken an at-bat since Tuesday, delivered a go-ahead two-out RBI single off Brent Honeywell. Outman followed with a homer to extend the lead to three runs.

“There’s nothing like it,” Busch said of getting a clutch hit in the Majors. “It’s very sweet to help this team get a win, especially in a place like this. It’s a tough place to win and getting two out of three here, I think that’s pretty big for the team.”

While it was the offense that came through late, that rally was made possible because of the stellar pitching performances from Julio Urías and the Dodgers’ bullpen. In the first inning, Urías wasn’t helped by his defense, as Betts and Outman both made misplays in the outfield. But that didn’t stop the Mexican left-hander from settling into the game and keeping the Dodgers within striking distance.

Urías worked through some traffic, ultimately allowing just two first-inning runs and striking out three over 5 2/3 frames.

“They know me, I know them. It’s a game that’s won by whichever side has the best game plan,” Urías said in Spanish. “That rivalry between us has been important. They have a great team, we have a great team.”

Heading into the weekend series, the Dodgers maintained their stance that this was just another matchup against a division opponent. They weren’t aiming to avenge last October’s postseason loss or prove something after the Padres’ busy offseason.

The Dodgers said much of the same after Sunday’s win. But one thing they learned over the course of the weekend was that the situation was becoming more heated in this newfound Southern California rivalry. The Petco Park scoreboard operator poked fun at Clayton Kershaw with a meme of him crying after Friday’s game, and a fan held up a sign during Saturday’s game aimed at Betts, which the right fielder promptly brought up during a postgame interview.

“100 percent,” Betts said, when asked if this series had more noticeable off-the-field moments than in the past. “Those are just tactics to try and get under our skins, make us act out of character. … We’re the ones that determine the games.”

Instead, those “antics,” as Betts called them, might have helped the Dodgers match the level of intensity the Padres have been playing with against Los Angeles since last year’s NLDS. When Kershaw was asked about the meme, the future Hall of Famer took the high road and argued those things wouldn’t happen if the Dodgers win.

They won’t say it publicly, but some of their actions suggest that maybe a trip back to Petco Park, the place their season ended six months ago, was just what they needed.

As Urías put it: “Whoever laughs last, laughs best.”