Jacoby Ellsbury follows through on a sacrifice fly that drove in Jason Varitek in the seventh inning for the Red Sox’ only run against Tampa Bay in Game Three of the ALCS yesterday at Fenway Park.

The Providence Journal / Glenn Osmundson

BOSTON — This wasn’t supposed to happen to the Red Sox.

Not with Jon Lester on the mound, especially at Fenway Park. Boston’s left-hander has become the ace of the staff in 2008, and the club was looking for him to dominate the Rays in Game Three of the American League Championship Series, as he did to the rest of the league during the regular season.

But that wasn’t the case last night.

The Rays pounded Lester for five runs (four earned) and eight hits, including two home runs, in 5 2/3 innings as Tampa Bay coasted to a 9-1 victory. The A.L. East regular-season winners now have a 2-1 series lead.

“I did (last night) what I said on (Sunday), that you have to stay away from,” said Lester. “They had a big inning (a four-run third that included a three-run homer by B.J. Upton and a solo homer to Evan Longoria), and that broke our back a little bit. You had to tip your hat to them because they did a good piece of hitting. B.J. turned on one that was over the plate, and I hung a cutter to Longoria. When you do stuff like that to good hitters, they are supposed to do what they did.”

What makes the southpaw’s subpar performance so unlikely was the fact that he entered the game with a 4-0 career mark and a 3.38 ERA against Tampa, including a 3-0 record and a 0.90 ERA this season. Not to mention his 11-1 record, with a 2.49 ERA, at Fenway this season.

The Rays were finally able to get to him last night in a big way.

“We didn’t bite on the pitches he wanted us to bite on,” said Upton. “He throws a lot of balls that start in the zone and end up out of the zone. We knew that coming in, and we were a lot more patient with him.”

While Lester downplayed the fact the Rays have seen him enough this season to get a good read on him, the Rays thought otherwise.

“Lester is one of the best left-handed pitchers in the league,” said Rays manager Joe Maddon. “We just had some good at-bats, and when he made a couple of mistakes, we took advantage of it. He is very good. Don’t be deceived. We just had a relatively good night. . . . We did go over him thoroughly, so we had a good idea coming in.”

Prior to this series, Tampa players had said they were thrilled that they weren’t facing Lester at Tropicana Field, because he has the ability to beat any team anywhere. If the Rays were going to lose to Lester, it might as well be in Boston.

It didn’t matter the venue last night, though.

“They capitalized when they needed to,” said Red Sox catcher and captain Jason Varitek. “They took some good swings. They got themselves into good hitters’ counts and got some good pitches to hit.”

Lester entered his third postseason start of 2008 without allowing an earned run in16 consecutive innings before Upton crushed his three-run homer in the third inning. Before that homer, Lester had held opponents scoreless for 24 2/3 consecutive innings in his postseason career.

“They came out swinging the bats great,” said Red Sox second baseman Dustin Pedroia, who went 2-for-3 with a walk. “They pitched good and played good defense. We didn’t do anything.”

On the other side, the Rays’ Matt Garza was outstanding.

Garza consistently reached the upper 90s on the radar gun, and when he did throw his off-speed stuff, the right-hander kept the Red Sox off balance. In fact, he allowed only four runners to get into scoring position, and only one scored. He finished six innings, and worked to two batters in the seventh, and allowed only one run on six hits, with three walks and five strikeouts.

“He gave up no runs in six innings and threw the ball great,” Pedroia said. “He did everything well. He pounded the zone and pitched great.”

Tampa also got to the Sox’ Paul Byrd in the eighth and ninth innings. Rhode Island native and Rays right fielder Rocco Baldelli crushed a three-run homer off the veteran right-hander in the top of the eighth, and Carlos Pena added a solo shot in the ninth for the final run of the game.

What makes the Rays so dangerous now is that not only did they gain a huge amount of momentum and confidence after Game Two, which they won, 9-8, in 11 innings, but now they’ve beaten Boston’s best pitcher at Fenway.

That isn’t how the Red Sox planned it.

jmcdonal@projo.com