BOSTON -- Red Sox manager Alex Cora called it "close to a perfect game" played by his team in defeating the Houston Astros 12-3 in Game 3 of the American League Championship Series on Monday night.

Once again, their offense was the story. It was dominant.

"Offensively, this is the best we've been the whole season, and they're locked in right now," Cora said after the Red Sox took a 2-1 series lead. "The preparation, it's a lot better right now. The communication is a lot better."

Cora is referring to pregame work his hitters are putting in, not only in the batting cage but in the clubhouse during meetings.

Everyone is contributing, and it's translating on the field, where first baseman Kyle Schwarber's second-inning grand slam, on a 3-0 pitch from Jose Urquidy, broke the game open on Monday.

It was one of 11 hits, giving the Red Sox six straight playoff games of 10 or more hits. That had never been done in a single postseason.

Boston also got home runs from Christian Arroyo, J.D. Martinez and Rafael Devers to go along with Schwarber's blast. It was his first career hit on a 3-0 pitch and first time in 17 plate appearances this season where he didn't walk after starting 3-0.

"I definitely wasn't thinking home run, but I definitely was thinking, don't be late and get it in the air," Schwarber said. "I'm a really bad 3-0 hitter."

His home run made it 6-0 after two innings. The Red Sox added three more runs in the third before Houston got on the board on a Kyle Tucker three-run homer in the fourth. But that's all the Astros would score on the night as Boston scored three more runs to seal the victory.

"We've got a collective group game plan, and we want to execute it with every at-bat, every pitch as much as we can," Arroyo said.

The six straight games of 10 or more hits is just the start of the Red Sox's offensive prowess.

• Boston has scored 50 runs in its past six games. That's the most by any team in a six-game span in the playoffs since Boston scored 52 runs over its final six games in 2007 to win the World Series.

• The Red Sox have 17 home runs in their past six games. That's the most ever over any six-game span in a postseason.

• They joined the 1998 Braves as the only team with three grand slams in a single postseason. They're the first to do it in a single series.

• They have scored 57 runs this postseason, more than the two NLCS participants, the Dodgers and Braves, combined (47).

Meanwhile, the Astros are searching for answers on the mound while pitching coach Brent Strom is concerned about his pitchers tipping their pitches.

"We just have to do a better job of watching what our pitchers do and getting ahead in the count," Strom said.

Cora believes it's the change in their hitting culture that has made the difference for the Red Sox. He credited Schwarber for bringing a new approach after his July trade to the team. Free-swinging hitters began to approach their at-bats with some patience.

"We were expanding," Cora said. "We didn't walk too much, and when he got here and when he started playing, it was different. It's a different at-bat, and other guys have followed his lead, and right now, like I said, this is the best I've seen this team this season offensively."