Brad Penny Sharp in Red Sox Debut

ANAHEIM, Calif. -- The Red Sox are still trying to figure out what they've got in Brad Penny, this All-Star turned No. 5 starter.

Catcher Jason Varitek, who caught all 86 of Penny's pitches in his Boston debut on Saturday, and manager Terry Francona both said they are feeling out Penny. Even after his six innings, he still seems like an unknown, albeit a promising one.

"We're still trying to figure out who he is, to learn him," Varitek said. "He's done a good job to get his work in and be where is at right now."

Penny knows what he has. He knew it the first time he threw a pitch in spring training and felt nothing in his shoulder.

"From the first pitch in the bullpen last year, every time I stepped on the mound I knew how bad it hurt and I was in for a long day," Penny said. "I was just trying to get through it. It's so much nicer to come out here and feel like I have no limits physically."

Penny got a late start in spring training because he was rehabbing his shoulder, but he said he's feeling 100 percent now.

"I did a lot of hard work with these guys," he said. "The spent a lot of extra time with me when I needed it. I feel it's all paid off."

He showed a glimpse of his old self -- the one who was an All-Star in 2006 and 2007 -- during his start against the Angels. In six innings, he gave up three runs, but he was better than that. One run was manufactured (a walk, a steal and two ground balls) and the other two came on two pitches, mistakes that Mike Napoli deposited over the fence.

For the most part, though, Penny was solid. He got more consistent in the strike zone as he got deeper into the game, and he even seemed to be throwing harder. His final pitch was a hard sinking 95 mph fastball that whiffed Kendry Morales.

The Red Sox won the thrilling game, 5-4, thanks to two homers by Jason Bay and a dramatic save for Jonathan Papelbon. Penny picked up the victory, his first since Aug. 8.

"He got into the flow of the game and he really competed," Francona said. "He did a pretty good job."

Even counting on nothing out of Penny, the Red Sox were one of the top teams in the American League. Now, if they could get even an approximation of his form from a couple years ago ... in the No. 5 spot ... look out.

"He's done everything we've asked," Francona said. "We'll get a better feel for him as we go, but right now we're thrilled to have him."