The slugging outfielder, aside from three cameo at-bats, has had to watch from the bench as his teammates have played the first eight games of the season.
"I'm excited, but I don't know about the weather," said Pena. "When I start my first game, that's going to be my Opening Day."
Red Sox manager Terry Francona, in an ideal world, would like to get Pena somewhere between 350-400 at-bats. But with an entrenched outfield of Manny Ramirez, Coco Crisp and J.D. Drew, that could be a challenge.
"I don't know, you never know," said Pena. "You never know what's going to happen. I just have to be ready. He told me that, so I hope they give it to me. I just have to be ready."
Pena has been putting in extra hours to stay sharp.
"I've been doing everything -- extra BP, just working hard, doing everything I can to stay in good shape," he said.
Of particular interest to Pena has been his work on his outfield defense. That paid off in the ninth inning of Tuesday's Fenway opener, when he caught the final out of the game by snaring a drive just in front of the short bullpen wall in right. In last year's home opener, Pena knocked a fly ball into the bleachers for a home run on an eerily similar type of play.
"I don't want to remember that one," quipped Pena. "It was the same play. Last year, I didn't know how to play this right field. I've been working hard out there. Especially in the Dominican, I was working on my defense. The first day of Spring Training, I told them I wanted to work on my defense, so we got [outfield instructor] DeMarlo [Hale] and we've been working hard so far."
Drew red-hot: Every year, there seems to be a player who has a red-hot Spring Training and then cools off as soon as the games start counting. Drew set himself up to be that person by having a terrific spring. However, instead of losing his stroke, Drew continues to spray line drives around the field with ease.
Boston's new right fielder came into Wednesday's game hitting .400 over 25 at-bats.
"J.D. is a good hitter," said Francona. "J.D., like every hitter, will go through a period where he slows down a little bit and everybody will be saying, 'What's wrong with J.D.?' Then he'll come back and be a good hitter. That's what good hitters do. Some guys should have shorter slumps than other guys.
"Part of the reason is his bat stays through the zone so well that he should eliminate some of those 0-fers because he stays on pitches that maybe other guys don't."
As hot as Drew is, Francona said he is still the player who will get Thursday off to make room for Pena.
"I think we need to, every 10 days or so, give him a day to not play," Francona said. "I think that's the best way to get production from him the whole year."
Lester takes another step: The Red Sox continue to get nothing but encouraging reports on left-hander Jon Lester, who is starting the season at Class A Greenville. Lester had five strikeouts and gave up three hits over four scoreless innings on Tuesday.
Lester will make two more starts for Greenville, after which point the Red Sox will determine the next step in his road back to Fenway.
"He's just begging for more innings. And he'll go to five next time out," Francona said. "His velocity was up a little bit, which is not surprising as he's gaining some endurance. He pitched well. I think he got up to 93 [mph] last night, which he hadn't quite done yet this year."
Timlin shakes off rust: Francona felt fortunate to be able to get Mike Timlin work in a blowout situation in his season debut on Tuesday. Timlin gave up two hits and two runs in closing out the 14-3 victory.
"He just threw a changeup to Richie Sexson that he knows he has to throw down in the zone a little better," Francona said. "We were talking about it during the game. I think we would have used him in a tight game because of who he is, but we were really pleased we were able to get him in a game like that first. I think Mike had some butterflies from not pitching yet. That was a good way to get him in there."
On deck: Knuckleballer Tim Wakefield draws the start in Thursday afternoon's series finale. He'll be opposed by Mariners left-hander Jarrod Washburn.
Ian Browne is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.