ST. PETERSBURG, Fla. - Cool and calm, or so it seemed.

Rookie Evan Longoria and the Tampa Bay Rays appeared perfectly at home in the playoffs with a Game 1 victory over the Chicago White Sox. Longoria said looks can be deceiving, though.

“I was nervous,” he said. “I think if you’re not nervous in this situation, you’re really not soaking in the moment.”

Tampa Bay’s All-Star third baseman homered in his first two at-bats and the surprising American League East champions were a big hit in their postseason debut, beating the White Sox 6-4 on Thursday to begin their best-of-five AL Division Series.

“He’s always got this way about him. He’s not going to be overwhelmed by the situation. And that speaks beyond his skill level,” manager Joe Maddon said. “Obviously, his skills are very good . . . and he likes these moments in a non-cocky way. He’s just very confident.”

After 10 seasons as baseball’s doormat, the Rays took the division with the best home record (57-24) in the major leagues. A lack of postseason experience was not a factor as they kept winning at Tropicana Field behind James Shields’ effective pitching and Grant Balfour’s testy, bases-loaded escape.

“It feels like you’re in a dream,” said Rays outfielder Carl Crawford, who at 27 is the longest-tenured player in team history. “I’m just glad we got this first win out of the way. It was real special.”

Tampa Bay ranked near the bottom of the attendance charts this year, but The Trop rocked on this day with a sellout crowd of 35,041 fans. Rays season-ticket holder Dick Vitale joined in the fun, waving a “We Love Longoria” placard from his first-row seat next to the visitor’s dugout.

Game 2 is today, when Tampa Bay’s Scott Kazmir (12-8) faces fellow left-hander Mark Buehrle (15-12).

“We want to win both of them now,” Longoria said. “We have such an advantage at home.”

Chicago beat the Minnesota Twins in the AL Central tiebreaker Tuesday and took a 3-1 lead on Dewayne Wise’s three-run homer in the third inning. But Javier Vazquez, who has a history of flopping in big games, could not hold it.

Longoria became the second player to homer in his first two postseason at-bats, joining one of his former minor league hitting coaches, Gary Gaetti, who did it with the 1987 Twins.

Longoria started the year in the minors and still hit 27 homers in the majors despite missing 30 games with a broken right wrist.

“This guy is a star. He’s going to be an outstanding ballplayer,” White Sox manager Ozzie Guillen said. “You see his face on the field, and you just know he’s going to be a great, great player.”

Longoria homered on his first postseason pitch, a 421-foot leadoff drive in the second. He put Tampa Bay ahead 4-3 with another solo shot in the third, a 430-foot homer off one of the infamous catwalks that support the roof at Tropicana. He also had an RBI single and went 3-for-3 with three RBI.

The Rays led 6-3 in the seventh when it got tense.

Balfour relieved Shields with the bases loaded and one out and struck out Juan Uribe. Orlando Cabrera was up next, and after ball one he kicked dirt toward the mound and appeared to shout something at Balfour. The reliever walked toward the plate before being stopped by umpire Joe West.

Balfour fanned Cabrera to end the threat, pumped his fist and pointed at the White Sox shortstop. The exchange brought Maddon and bench coach Dave Martinez out of the dugout and more words were exchanged.

Cabrera said he responded to something Balfour said.

“They say that he always gets pumped up like that,” Cabrera said. “I didn’t know that so I just got mad a little bit and I was just pumped up. It was just heat of the moment.”

Said Balfour: “I fire myself up. That’s what I do. I haven’t changed anything. I’m not going to change.”

It was the same kind of feisty attitude the Rays displayed in spring training during a dustup with the New York Yankees and a bench-clearing brawl in June on their first visit to Boston to play the Red Sox.

Shields allowed three runs and six hits in 6 1/3 innings. Balfour struck out both batters he faced and J.P. Howell worked a perfect eighth.

Dan Wheeler gave up a solo home run to Paul Konerko in finishing for a save.

Tampa Bay slugger Carlos Pena left after the second with slightly blurred vision in his left eye. The Rays said he accidentally scratched his eye at home and was expected to return to the Game 2 lineup.

Longoria’s RBI single in the fifth made it 5-3 and chased Vazquez. Crawford, back in the lineup for the first time since he injured his finger on Aug. 9, hit an RBI single off Clayton Richard.

Vazquez allowed six runs and eight hits in 4 1/3 innings - the fourth consecutive start, all losses, he’s gone less than five.

“We have to win tomorrow,” Guillen said. “I mean, it’s not a do-or-die thing, but I’d rather go home with one win than go home with our backs to the wall. This organization has been against the wall a lot of times, but we’ve pulled it out before."