BOSTON -- Guided by a sure-handed starting rotation, the Red Sox regained their footing in the American League East race on Monday and Tuesday against the Devil Rays. However, on Wednesday, they tripped and couldn't recover against a 24-year-old rookie with a funky delivery.

Rays starter Andy Sonnanstine, a 13th-round pick in the 2004 First-Year Player Draft who entered the day with a 1-8 record and a 6.35 ERA, reached back and found his best stuff opposite Daisuke Matsuzaka at Fenway Park. Slinging strikes from angles high and wide, Sonnanstine silenced the Red Sox until he stumbled in the seventh inning. And yet, despite scoring five unanswered runs over the final three frames, Boston fell short, 6-5, in the series finale.

"I wish we'd done a little better job in the first six innings," said Mike Lowell, whose seventh-inning single ignited a two-out rally. "It seems like we came out a little flat."

Only in the seventh did Sonnanstine allow multiple baserunners in an inning, when Jason Varitek curled an arcing liner around Pesky's Pole in right field with a two-run homer.

Then, Sonnanstine walked Coco Crisp and yielded control of the mound and a 6-2 lead to the league's worst bullpen. It was then, on a day that the Yankees forced extra innings against the Orioles before falling in the 10th, that things got interesting in Boston.

Before the close of the seventh, Rays reliever Gary Glover allowed an RBI double to Julio Lugo. The Red Sox added a fourth run in the eighth, pulling within two.

Rays closer Al Reyes entered the game for the second straight day, eager to atone for a blown save on Tuesday night. Crisp led off the ninth by deadening a bunt down the third-base line. He reached without a throw. Lugo followed with an 11-pitch at-bat, ending it with a pulse-pounding RBI double.

"He threw me some good pitches," Lugo said. "I was fortunate just to foul them off."

With speed on second and no one out, Reyes struck out Dustin Pedroia and Kevin Youkilis in succession. David Ortiz walked to first, and Manny Ramirez sauntered to the plate, representing the winning run.

Reyes fired a high fastball past Ramirez, corkscrewing the Red Sox star into the dirt. Final score: 6-5.

"He is an absolute pro," said Rays manager Joe Maddon of Reyes, who picked up his 18th save. "You could see him out there, and he was never riled."

Matsuzaka squandered an opportunity to become the team's third 14-game winner when he exited after the sixth. He allowed six earned runs, four during a critical third-inning rally, on eight hits and three walks.

"I'm very disappointed," Matsuzaka said through his translator, "and even sorry that I put a stop to our momentum today."

"We can give him some leeway," said Lowell of Matsuzaka, who entered the game with a 1.93 ERA in August, "but I'm sure he would've preferred to execute his pitches a little bit better. But, you know, that's the way it goes sometimes."

Despite the Red Sox's late rally, the day ultimately belonged to Sonnanstine, a Kent State University product who had never the Red Sox and allowed four hits and three earned runs in 6 2/3 innings. Until the sixth, only Lowell and Varitek had reached base for the Boston, both on two-out hits. Until they rallied in the seventh, the Sox faced a 6-0 deficit.

"His ball was cutting good," Lowell said. "He doesn't really throw anything straight."

"He has a little funkiness to his delivery," Varitek said. "But he did a good job."

With that, the Red Sox fell short of closing out a series sweep. What's next? The first-place Los Angeles Angels of Anaheim will come to Fenway Park for a Friday day-night doubleheader.

"We're just looking forward to another series," Varitek said. "Hopefully, we keep this momentum of fighting through games and carry it through the whole weekend."