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The final act in the dreadful season of the Boston Red Sox is being played at Yankee Stadium. And the first scene of the last series was another ugly lowlight in a year filled with them.

Robinson Cano, Curtis Granderson, Russell Martin and Mark Teixeira homered in a nine-run second inning Monday night, leading the New York Yankees to a 10-2 rout of the Red Sox and Clay Buchholz.

While the Yankees opened a one-game lead over Baltimore in the AL East with two games to play, Boston clinched at least a share of last place in the division. The Red Sox, two games behind fourth-place Toronto with two to play, hadn't finished in the cellar since 1992.

"The season as a whole, everybody's got to learn from it. I don't think anybody in this clubhouse is happy about the position we're in right now," Buchholz said. "But we've got a lot of key guys who have been hurt throughout the season for a period of time and that takes its toll. It hasn't been the standard here that everybody expects of us. Like I say, we've got to learn from it and hope it leaves a bad taste in everybody's mouth."

Starting what may be its final series under first-year manager Bobby Valentine, Boston has lost six in a row and 10 of 11, reaching 91 defeats for the first time since dropping 100 games in 1965. In what resembled a spring training lineup, the Red Sox started just two regular position players, Cody Ross and Jarrod Saltalamacchia. Six of the starters had uniform Nos. 50 or higher.

"You play the cards that you have," Valentine said. "That's all we have right now."

Dustin Pedroia was out because of an injured finger, and Jacoby Ellsbury sat against left-hander CC Sabathia after returning from an injury last weekend.

Buchholz (11-8) was roughed up for eight runs and six hits — three of them homers — in 1 2-3 innings. He dropped to 0-5 with a 5.62 ERA in his last eight starts.

"I felt as good today as I've felt the second half of the season. The ball was coming out fine," he said. "It's tough whenever you pitch in the middle of the plate and everyone gets hit. That's what this team is known for. They hit mistakes and they got them out."

The eight earned runs off Buchholz were a career high.

"Well, they didn't miss any of his mistakes," Valentine said. "He's out there giving it everything he had. It's just a tough lineup to make some mistakes to. They were able to hit him hard."

Daniel Nava homered against Sabathia (15-6) leading off the fourth, and Saltalamacchia hit a sacrifice fly in the seventh.

New York (93-67), which clinched its 17th playoff berth in 18 years on Sunday, would ensure its 13th division title in 17 years by sweeping the three-game series against the Red Sox. Baltimore (92-68) lost 5-3 at Tampa Bay and dropped into second place.

"There's a lot of teams that would love to be in our position right now," Teixeira said. "You can count all of the things that have gone wrong but, hey, we're right here where we want to be. And if we keep winning, we'll be division champions and have a chance to make a run in the playoffs."

New York tied its record for home runs in an inning, achieving the feat for the third time. Sabathia (15-6), with perhaps his best changeup of the year, allowed two runs and four hits in eight innings with seven strikeouts and a walk. Following a stretch of four shaky outings, he is 2-0 with a 1.50 ERA in his last three.

"I'm just trying to relax and not overthrow," he said.

NOTES: Valentine said Pedroia is uncertain for Tuesday. "He couldn't swing before the game. We'll see how he is tomorrow. No one goes to the post like Dustin. If he's capable of playing, he'll be in there tomorrow." ... Ellsbury was 1 for 8 on Saturday and Sunday after being sidelined since Sept. 20 with an unspecified injury. He is 6 for 28 (.214) against Sabathia. "He'll play the next two days, hopefully, if he's feeling good," Valentine said. ... Boston is 5-11 against the Yankees, its most losses against New York since 2006.