BOSTON — The Boston Red Sox brushed aside the 100-win Los Angeles Angels in four games, dismissing their best-in-baseball regular season as last month's news.

When it turns to October, no one dominates like Boston.

Jason Bay scored with a headfirst slide on Jed Lowrie's two-out single in the ninth inning and the defending World Series champions took advantage of a botched suicide squeeze, beating Los Angeles, 3-2, last night to win their first-round playoff series in four games.

Boston, which also won it all in 2004, will have a chance at a third title in five years if it can get past the Rays in the best-of-seven AL Championship Series that starts Friday night at Tampa Bay.

"That's what this team is about, especially the last few years," said Lowrie, a rookie who was called up as a midseason replacement when shortstop Julio Lugo was injured. "It's October, they've won a lot of games, and to be a part of that is awesome."

The AL's youngest team, Tampa Bay had never finished better than last in the division and posted the worst record in baseball last year, while Boston, one of the league's charter members, was winning its seventh championship. But in just 11 years, the Rays and Red Sox have become fierce rivals, with the latest bench-clearing brawl coming at Fenway Park in June.

"I can't wait to get it going," pitcher Josh Beckett said. "But we've got a few days off to enjoy this."

Los Angeles was able to force the series to a fourth game with an extra-inning victory Sunday night that snapped an 11-game playoff losing streak against Boston.

"Those guys have certainly, in the last three series that we've been involved with them, they've beaten us," Angels manager Mike Scioscia said. "I thought we played much better this series than going back to '04 or '07 against them. It's naturally disappointing. But we're going to have to keep trying to get better. That's all we can do."

Jon Lester held the Angels to four hits in seven shutout innings but lost his chance at a second victory in the series when they scored twice in the eighth to tie it 2-all. Los Angeles had a chance to go ahead in the ninth before Erick Aybar, whose 12th-inning single was the winner in Game 3, missed on a squeeze attempt.

In the bottom half, Bay lofted a fly ball down the right-field line that Reggie Willits pursued and dived for before it one-hopped into the stands for a ground-rule double. First baseman Mark Teixeira made a diving catch of Mark Kotsay's line drive for the second out.

Again, it was only a temporary save.

Lowrie grounded a single into right, and Bay raced around third and slid headfirst ahead of the throw while his teammates poured out of the dugout to celebrate.

It's been a common sight in Boston, but one Bay had never taken part in before he was acquired from Pittsburgh when the Red Sox unloaded Manny Ramirez at the July 31 trade deadline.

"The only thing I'm thinking is, 'Get a good jump and don't fall down around third,"' Bay said. "I can't imagine that it'll get more intense than this, but it will."

Manny Delcarmen got two outs in the ninth for the win, squelching the Angels' chances to take the lead by getting Aybar to whiff on a bunt try with one out and a runner on third. Red Sox catcher Jason Varitek, whose passed ball helped Los Angeles tie the game in the eighth, pursued pinch-runner Willits back toward third and made the diving tag a step before the bag.

Varitek lost the ball as he hit the ground, but third base umpire Tim Welke ruled that he had already applied the tag. Scioscia argued, but replays showed that the out was recorded before the ball came loose.

Scot Shields took the loss, allowing two hits and a run while striking out three in 1 2/3 innings.