BOSTON – John Lackey settled down after a shaky start with big assists from his slick-fielding second baseman and his hard-hitting teammates.

With the bases loaded and no outs in the third, Dustin Pedroia stabbed a sharp grounder by Casey McGehee to start a double play on which a run scored, tying the game at 4, but the play took the steam out of the rally.

“That’s going to be a couple of runs, maybe second and third,” Boston Manager Terry Francona said after the Red Sox beat the Milwaukee Brewers 10-4 on Friday night. “That was the biggest play of the game.”

Lackey then retired the next 14 batters, with only two getting the ball out of the infield, and the Red Sox won for the 12th time in 13 games.

“Any time it goes Pedey’s way, you have a chance,” Lackey said. “He’s the best.”

So are the Red Sox hitters. They lead the majors with a .274 batting average after pounding 14 hits, three each by Adrian Gonzalez and David Ortiz.

“That’s one thing you can hang your hat on when you’re out there,” said Lackey (5-5), who is 3-0 since coming off the disabled list.

“If you give up a couple of runs, hang in there because the boys are coming. They can really swing.”

The hitters got a break when the Brewers were forced to go to their bullpen early after Shaun Marcum left following the first inning with a strained left hip flexor. He had given up two runs on four hits and was replaced by Marco Estrada (1-4), who allowed a go-ahead homer to Gonzalez that gave Boston a 5-4 lead in the fifth.

Marcum thinks he’ll be able to make his next scheduled start.

“I didn’t want to come out after the inning, but we wanted to be smart about it,” he said. “I’ll come in (Saturday) and see where we’re at. Hopefully, the tightness will be out of there for the most part.”

Boston increased its AL East lead to 2½ games over the New York Yankees, who lost 3-1 to the Chicago Cubs.

Lackey gave up four runs before getting an out in the third. Then Pedroia started the double play after four consecutive singles by Rickie Weeks, Nyjer Morgan, Ryan Braun and Prince Fielder.

“Huge play,” Milwaukee Manager Ron Roenicke said. “We’ve got a chance to have a big inning there and it’s not the first time I’ve seen him do it. The guy can play.”

The Red Sox’s potent offense resurfaced after they scored just seven runs in a three-game series at Tampa Bay, although they won two of them. During their nine-game winning streak going into that series, they averaged 9.2 runs.

Milwaukee’s fourth loss in five games ended with a perfect ninth by Matt Albers, who struck out two batters.

The Brewers scored two runs in the first on a single by Morgan, a double by Fielder and a two-run single by McGehee.

Lackey “was throwing the ball well” from the start, Red Sox catcher Jason Varitek said. “He made one mistake in the first inning and McGehee did a nice job of hitting.”

Roenicke was bench coach for the Los Angeles Angels the past five seasons — the first four of them with Lackey on the team.

The Red Sox tied it in the bottom of the first on a leadoff homer by Jacoby Ellsbury, a single by Gonzalez and an RBI double by Ortiz.