Both Seager brothers homered in their first MLB game against each other, but the rest of the Dodgers outslugged the rest of the Mariners on Monday night in a wild 11-9 win in the bandbox at Dodger Stadium.

“We obviously needed every run we could get,” said Dodgers manager Dave Roberts. “The at-bats we took all night long were great. The ball was flying more than it typically does. But our ‘pen came through big and picked us up.”

• Box score

Dodgers shortstop Corey Seager was 2-for-4 with a three-run homer and walk, while Seattle third baseman Kyle Seager was 3-for-4 with a solo homer, walk and stolen base. Before the game, Corey said he hoped Kyle would get four hits and the Dodgers would win. That was just about the script.

“It was a special night, for sure,” said Corey, who also hit a three-run homer on Sunday.

Combined, the Seager family was 5-for-8 with two homers, five RBIs, four runs, two walks and a steal. Mom and Dad Seager, take a bow.

“Corey matching his brother blow to blow, the game within the game, that was a lot of fun,” said Roberts.

With each Seager smirking at the other on their home run trots, they became the first brother act to homer in the same MLB game since Cesar (San Diego) and Felipe (San Francisco) Crespo on June 7, 2001. The last pair of brothers to homer as teammates in a game was Justin and B.J. Upton on Sept. 27, 2014, as members of the Braves. Kyle Seager also stole a hit from Mookie Betts with a diving play.

“It was hard almost to stay focused with him out there, you want to go talk to him,” said Corey. “And he’s a talker, he wanted me to go over there. You try to be in the moment as much as possible. You’re still trying to win a game. But when you got around him, it was hard to not see your brother in the opponent. Really enjoyed it, one of those things we’ll remember for a long time.”

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The Seagers keep it interesting with side bets and in this game, it was for first home run. Corey’s came in the second inning, Kyle’s in the third, but it was the second at-bat for both.

“I’m going to go with a push,” Corey said.

Erupting for a pair of five-run innings, the first-place Dodgers extended their win streak to six, while last-place Seattle’s losing streak reached six. Kenley Jansen, after putting runners on first and second with no outs, secured his seventh save.

The Dodgers have outscored their opponents, 45-12, after the seventh inning this year, and it’s no real mystery why. Their hitters are better than opposing relievers, and their relievers are better than opposing hitters. So, when games get into the bullpen, it’s no contest, and that’s how the Dodgers feel.

“I do, and most importantly, the guys in that room back there feel that way,” said Roberts. “They feed off each other. When they continue to grind, swing at good pitches and put pressure on that reliever coming out of the ‘pen, good things are going to happen. I’d like to think that the focus isn’t more dialed in late in games, but sometimes late in games you turn it up just a tick more. Our guys do a good job at the end of the game.”

In addition to Corey Seager, the Dodgers got home runs from Betts and Enrique Hernández. Betts homered leading off the bottom of the first inning, his 21st leading off and first as a Dodger. Betts has seven homers in his last 11 games and nine on the year.

The Mariners slugged three home runs in the third inning, Kyle Lewis and Kyle Seager going back to back, and one out later Evan White launched a two-run shot, his first of two home runs. Those homers came off Dodgers starter Ross Stripling, who allowed seven runs (six earned) in only three innings and let a 6-2 lead get away. Stripling allowed two homers in his previous start, including a Manny Machado grand slam.

Corey Seager triggered the comeback with a single leading off the seventh, the rally aided when Seattle second baseman Shed Long Jr. couldn’t glove Justin Turner’s foul, which Turner followed with a single. AJ Pollock singled in a run and Max Muncy walked with the bases loaded on a check swing to tie the game. Joc Pederson’s double-play grounder broke the tie and Hernández’s two-run homer padded the lead.

Despite the three home runs, Roberts said slumping Muncy, who had three walks and a lineout, had his best all-around game offensively.

“He understands the value of 90 feet,” said Roberts. “He understands the value of slug. But when you’re not getting hits, you have a tendency to chase hits. For him to chase a quality at-bat and get on by walk three times, I tip my hat to him.”