Decisions have been made for him

Penny proved that again last night with 6 1/3 effective yet unremarkable innings in a 7-3 Red Sox victory, a performance good enough to earn his third win in four decisions. He allowed three runs on eight hits and two walks with two strikeouts.

When the Red Sox erupted for five runs in the sixth, there was Penny, still pitching well enough for another victory.

"Any time you can keep the game close with this team," Penny said, "you've got a chance to win."

Penny earned the a spot in the starting rotation after he proved his shoulder was strong enough for it during spring training. He held off Clay Buchholz despite Buchholz having perhaps the best spring of any Red Sox pitcher. As Buchholz said this week in Pawtucket, "It's hard to spend $5 million and say, 'Well, he's doing a little bit better than you, so we're going to let him take the spot.' "

Penny continues to hold Buchholz off, even as Buchholz continues to tear through Triple A. Last night, while Penny beat the Rays, Buchholz allowed one hit in seven shutout innings and struck out eight in a 4-0 victory at Columbus. Buchholz has allowed one earned run in his last 18 1/3 innings, and he's held opponents to a .126 batting average this season. Buchholz's spring indicated he had left last season's horrors behind, and he proved as much during the early season.

Penny hasn't matched that brilliance, but he's been good enough. Four of six starts have registered as quality starts, for which the minimum standard is three runs and six innings. Penny has allowed exactly three runs in exactly six innings in half of his starts. Last night, for a departure, he allowed three runs in 6 1/3 innings.

Penny's record is 3-1, but his ERA is 6.90. Maybe the best way to put it is that Penny has done his job well enough to keep it.

"He's done an OK job," Sox third baseman Mike Lowell said. "I think he wants to do better, and he's capable of doing better. His command was better. He was down in the zone more. When he throws strike one, it makes people think a lot more."

Penny's start last night fit cleanly into the pattern of his season. He allowed a run in the first on two hits and a walk, and he needed 31 pitches to escape the inning. The game moved along, and the Rays scored once in the third and once in the fourth. He settled in. His fastball hummed at 95 miles per hour, but he did nothing spectacular.

Rays starter James Shields cracked in the sixth. Penny never did. By the seventh, he still was pitching and the Red Sox were winning.

"His last few innings I thought were outstanding," Lowell said. "He was throwing strike one, getting a lot of one-pitch outs. He ended up having a nice quality start. Throwing into the seventh for us is big."

Penny faced a unique challenge while he did it. Only five days prior to last night, Penny faced the Rays at Tropicana Field. The Rays knew exactly what they would get.

"I think you've got to stick with your game plan," Penny said.

"You hear both sides of it, but it's just as much an advantage to me as it is them. I think I know their weaknesses, and they know mine."

Said Lowell: "It's not easy facing the same team two consecutive starts. I don't think that is an advantage for the pitcher."

Penny has the capacity to be more than a fifth starter who ekes out wins. He started Opening Day last season, once started the All-Star Game (2006), and has thrown in high 90s.

Twice this year, Penny hasn't thrown a pitch past the third inning, and he seemed headed for another short stay last night. Penny has the misfortune of being more spectacular in defeat than victory this season, but more often than not he has found a way to win.

"Any time you go out there and get your team behind in the game in the first inning, it [stinks]," Penny said. "But they came back, we hung in there, and they pulled it through for me."

Adam Kilgore can be reached at akilgore@globe.com