Dodgers defend Corey Seager swinging on 3-0 pitch, which Don Mattingly blames for skirmish

In the seventh inning on Friday night, Dodgers shortstop Corey Seager watched as Marlins reliever Nick Wittgren opened an at-bat with three consecutive balls. From the dugout, Dodgers manager Dave Roberts allowed Seager to swing away at the next pitch. His team led by five runs. Roberts did not see much harm in the decision.

Inside the opposing dugout, the sight of Seager taking a rip at the next pitch upset Miami manager Don Mattingly, who had held the same title in Los Angeles from 2011 to 2015. It was not the result that bothered him. Seager fouled off a pitch and eventually took a walk. It was the impudence of the decision, Mattingly would hint later in the night.

The moment seemed small. But Mattingly pointed to it after a benches-clearing skirmish in the ninth. An inning after Seager swung at the 3-0 pitch, Dodgers rookie Cody Bellinger blasted a home run off Marlins reliever A.J. Ramos. Ramos drilled the next batter, outfielder Brett Eibner. In the top of the ninth, Dodgers reliever Ross Stripling used his first pitch to throw behind hulking Marlins outfielder Giancarlo Stanton.

The two teams met in a rugby scrum near home plate when Stanton approached Stripling on the mound.

In the aftermath, Ramos and Stripling both denied pitching with an intent to hit people. Roberts suggested the matter was squashed. But Mattingly mentioned Seager’s swing as a catalyst. A day later, before Saturday’s game at Dodger Stadium, Roberts disagreed with his predecessor’s sentiment.

“I had no idea that he took offense to it,” Roberts said. “There’s things in baseball, we talk about unwritten rules and how you play the game. If things were switched, and the tables were turned, I would have no problem with those guys swinging 3-0 in the seventh inning.”

The unwritten rules, in theory, suggest passivity for teams on offense after achieving a significant lead. If leading by five runs in the seventh inning, batters should not try to bunt for a hit or steal bases or swing at 3-0 pitches. This theory is considered by many managers to be somewhat antiquated.

Roberts pointed to the events in the top of the eighth: Alex Wood, after cruising most of the evening, allowed a pair of singles to start the inning.

The Marlins stood on the verge of pressuring the Dodgers into using their high-leverage relievers. Roberts had used Kenley Jansen for a four-out save in the previous game, and did not want to tax him unnecessarily.

Thus, Roberts felt, the offense needed to continue to compete. The effects of one game can bleed into another.

Last week in Colorado, the Dodgers fell behind by 10 runs. But a comeback in the ninth forced the Rockies to use closer Greg Holland.

Moments like that have merit in a series, Roberts said.

And it would not be fair to Seager to restrict him in that situation.

“He earned an opportunity to get into a hitter’s count,” Roberts said. “And so, to concede that, at that point in time, with respect to the score, I didn’t feel appropriate.”

Once the two sides gathered on the field, Mattingly charged toward Dodgers bench coach Bob Geren, his teammate with the Yankees from 1988 to 1991. Mattingly was furious that Geren yelled in the direction of Stanton after the benches cleared.

“When he’s out there yelling at my guy, he’s going to have to go through me,” Mattingly said. “If the players are going to yell and get after it [that’s one thing]. But when he’s going to start yelling at guys, it’s a whole ’nother thing.”

Friday marked the second time this week that the Dodgers have engaged in an incident like this.

The team went through a less intense version on Wednesday, when catcher Yasmani Grandal jawed with San Francisco starting pitcher Johnny Cueto. Cueto became upset when he felt Grandal and his teammates were stealing signs.

andy.mccullough@latimes.com

Twitter: @McCulloughTimes