CHICAGO -- After he allowed four runs to the Red Sox in the first three innings in Game 2 of the American League Division Series, Mark Buehrle knew that he had to make an adjustment, and it had to come quickly.

The Red Sox weren't exactly tattooing the left-hander, but they were collecting just enough hits to the opposite field to get their powerful offense going. So Buehrle decided to make a change in plan.

"Throw it down the middle and let them hit it harder so that they would hit it to my defense to get outs," Buehrle said of the adjustment he made.

If that was the case, Buehrle didn't quite inform his catcher of the plan.

"I didn't see it like that," A.J. Pierzynski said when told of Buehrle's explanation. "I wish he would have told me that, because I wouldn't have tried so hard to get him to hit the corners."

Whatever the change, it worked as Buehrle went on to pitch four more innings, holding the Red Sox scoreless as his teammates rallied for a 5-4 victory to take a 2-0 lead in the series.

Another five-run inning from the Chicago offense may have played a large role in the victory, but White Sox center fielder Aaron Rowand said it was the change in Buehrle that really was the key to the win.

"That was probably the biggest story of today," Rowand said of Buehrle's performance. "He got roughed up in couple of innings, but he went out there and found himself and started making pitches. He stayed in the game and gave us an opportunity to come back."

The difference in Buehrle's performance after the third inning was staggering. The pitcher faced 15 batters over his first nine outs before settling down to get 12 of the next 14 hitters out over his final four innings.

In his two previous outings this season against the Red Sox, Buehrle had seen his share of troubles. With an 0-1 record and a 6.23 ERA in those two starts, it seemed like the same problems would haunt the left-hander again -- except this time on a bigger stage.

But Chicago's problems in the early going weren't entirely because of Buehrle; manager Ozzie Guillen admitted that his characteristically strong defense let down the pitcher in the first few innings.

"I think we made those plays before," Guillen said, "but Buehrle was also up a little bit [in the zone]"

Both Guillen and Pierzynski agreed that Buehrle wasn't hitting his spots during those first couple of innings and both blamed a case of the nerves as part of the reason. Though the veteran lefty has had plenty of experience in key regular-season games, his time in the postseason had been limited to only to one-third of an inning in a relief role.

Buehrle, though, didn't feel it was nerves as much as it was adrenaline that may have caused him to be a little off. Despite some butterflies heading into the start, Buehrle said that the nerves had quieted by the time he reached the ballpark.

"When I woke up this morning, I was really nervous," Buehrle said. "Once I got to the field and I got around the guys and loosened up, I didn't feel any nerves at all."

Nerves or not, Buehrle was a different pitcher once the runs were on the board, and Pierzynski said that the slight adjustments that the two made -- not just throwing hard -- made a big impact on the pitcher's demeanor.

"We tried some different stuff," Pierzysnki said. "Throwing some different pitches on different counts and going from there. It seemed to settle him down. Once he gave up some runs, he relaxed and got back to being Mark."

"Being Mark" meant earning the first postseason victory of his career. Though Buehrle was happy to pick up his first win over such a tough offense, he hopes his team will grab at least one victory over Boston in the two games at Fenway so he won't have to try to get No. 2 against the same squad.

"I'm just fortunate that we're up 2-0, and hopefully we can just sweep these guys so there is no chance I have to face them again," Buehrle said.