NEW YORK -- One day after he was surprised to see his name not in the lineup for the opener of the Yankees' four-game series with the Red Sox, Jorge Posada said he's adapting to playing a little less now that the team has added Lance Berkman at designated hitter.

"I didn't look at it as it's going to affect me," said Posada. "[It's just] try to get everybody involved, the whole lineup involved."

Posada has made 24 of his 70 starts as the DH this season -- well beyond his previous career-high of 15 games as the DH set in 2008. Since his return to the backstop in early June, Posada had settled into a routine of catching roughly three of every five games and serving as the DH the majority of the time otherwise. That changed when the Yankees acquired Berkman, who has played in five of the team's six games since the trade. Even when Berkman doesn't get the nod against left-handed pitchers, it appears Marcus Thames will start more at DH.

"We've had a rotation here with our [starting] rotation, and it's been successful and it's pretty much what I'm going to stick to," manager Joe Girardi said. "[Francisco Cervelli has] caught Javy [Vazquez] and A.J. [Burnett] mostly, and I've stuck to that rotation because it's been successful."

Girardi said he is hesitant to catch Posada more often because the 38-year-old tends to aggravate nagging injuries the more he plays behind the plate. Posada missed the entire four-game series in Cleveland with a cyst behind his left knee after he had caught nine of the previous 13 games.

"I've got to deal with it," Posada said of the cyst. "I've got to treat it, I've got to get it ready to play. But it's good. It's better than it was in Cleveland."

Although he prefers to earn his playing time behind the plate, Posada said he doesn't mind being the DH.

"I enjoy playing, DHing," he said. "I'm not against it."

Granderson looks to get on hot streak

NEW YORK -- Before Saturday's 5-2 win over the Red Sox, manager Joe Girardi commented on the ups and downs of center fielder Curtis Granderson.

"He seems to be somewhat streaky, and right now, he's not in one of those streaks where he's getting a lot of hits," Girardi said. "He needs to get in one of those streaks again."

Consider Saturday an auspicious start.

Granderson sparked the Yankees offense with an RBI triple in the second and created a run on his own in the sixth, when he hit a leadoff single, stole second, took third on an error and scored on a Ramiro Pena single.

"I'm just trying my best to do things to help the team," Granderson said. "Just trying to get it done, with a big spark plug today like the triple or something small like a routine defensive play or a good at-bat. The main thing is throughout the course of a nine-inning game trying to help this team win ballgames."

Granderson does appear to be a player whose game is characterized by flashes -- of his leather, of his speed and of his power. As such, his best stretches this season have tended to be explosive but ephemeral. His longest hitting streak is five. He has nearly as many multihit games (22) as he does with just one hit (25). He has homered three times since June 24, and all three came in a two-game span at the end of July.

Girardi and the Yankees now aim to make those flashes a more sustained source of light.

To understand what a revived Granderson toward the bottom of the order would mean, one need only look at how integral a piece Brett Gardner has been for the Bombers' offense this season. Despite spending the majority of his time in the order's bottom third, Gardner was near the top of the American League leaders in runs scored. He, however, has struggled since the end of June. The Yankees' offense could use the that type of production from Granderson, who possesses most of Gardner's speed with the added element of power.

Struggling Berkman confident he'll turn it around

NEW YORK -- Lance Berkman was able, mostly, to laugh about it after the fact. But the recently acquired designated hitter knew that hitting Alex Rodriguez during batting practice wasn't going to earn him too many fans with his new team.

"Berkman's contributions to the Yankees so far have been not the greatest," Berkman said.

Indeed, Berkman's time in the Bronx was already off to a rough start, and that was before his hard one-hopper in BP knocked the Yankees' cleanup hitter out of Saturday's game. He followed it up with another hitless performance in New York's 5-2 win over Boston, leaving him 2-for-22 since donning the pinstripes.

Berkman's struggles at the plate have subjected him to some boos at his new home ballpark. It's something the veteran expected and understands.

"This is a big boy's game and place to play, and if you can't handle a little bit of that, you can go home," Berkman said. "It's not personal. I'm booing myself right now."

"My sense with Lance Berkman is it's not going to bother him," manager Joe Girardi said. "He's an experienced player who's had a lot of success. He's been in a slump before, and he's pretty even keel."

Earlier in the week, Berkman had compared coming to a new team to getting your first callup to the Majors -- you have little credibility with the fans. Even with his All-Star pedigree, that's a comparison he reinforced on Saturday.

"You have to earn the respect of the fans, and you're not going to do it by not hitting. You're only going to earn their ire," Berkman said. "I have no credibility here. I've done nothing."

That said, he added that being a veteran with a track record helped him personally, since he knows that, eventually, he should come out of his current malaise.

Berkman, though, was already having a subpar season with the Astros. A career .296 hitter, Berkman is batting only .234 in 2010. He's hoping the trade can revitalize him after slogging along toward the bottom of the National League Central in Houston the last few seasons.

"I didn't come up here to catch a break. I came here to play well and win," he said. "I'd love to get to a place where I can be part of the machinery that drives this thing."

The 34-year-old, though, did admit that further slumps at the plate this season might force him to contemplate the idea of retirement in the offseason.

"If I stink for these two months, that's definitely going to make me take a good, hard look at where I am physically," he said. "I'm not getting any younger."

Pettitte to throw another bullpen session

NEW YORK -- Andy Pettitte will throw a full bullpen session on Monday as he continues his recovery from a strained left groin.

Pettitte threw a bullpen session on Friday but admitted that he was cautious pushing off with his injured left leg during his first 20 pitches.

"I hope to get on there 100 percent, just like my warmup would be," Pettitte said. "And then I hope to sit down, get back up and do a simulated inning."

If everything goes well on Monday, Pettitte would then head down to Tampa for a simulated game on Thursday or Friday. Pettitte is confident enough in his health that he was planning to pack his bag and send it to Tampa on Saturday. If there are no setbacks down south, Pettitte can begin a rehab assignment as early as Aug. 16.

Manager Joe Girardi said that the team isn't worried about lining up Pettitte's rehab starts with his turn in the rotation, currently occupied by Dustin Moseley.

"When Andy's ready, Andy will pitch. If we have to get guys an extra day of rest, that's fine," Girardi said. "The most important thing is when Andy's healthy, that's when he'll pitch as opposed to trying to just line it up."

Worth noting

The Yankees' four-game streak of hitting a two-run homer in the first inning ended on Saturday. The four consecutive games with a multirun homer is a franchise record and the longest in the Majors since the Rockies pulled the trick in August 1995, according to the Elias Sports Bureau. The Yankees were, however, 1-4 in those five games. ... The Yankees have dropped three straight series openers for the first time all season.