But as soon as they went into their tightly knit clubhouse, they celebrated like rowdy schoolboys.
There was a collective sigh of relief as All-Star first baseman Paul Konerko leaped to catch Placido Polanco's line drive with the tying run at first base to end the game.
Their subdued on-field celebration was marked by mild hugs near the pitcher's mound, and then they erupted in a clubhouse as champagne corks popped.
Longtime trainer Herm Schneider soaked Chairman Jerry Reinsdorf, and Detroit general manager Dave Dombrowski, a former Sox administrative assistant, congratulated Sox general manager Ken Williams and manager Ozzie Guillen.
It was a fitting celebration for a retooled team that stunned the baseball world by staying in first place in the division throughout the regular season but nearly squandered the 15-game lead it had on Aug. 1.
The Sox's pitching staff and reinforced defense carried them most of the way, but their approach was ripped when the offense slumped during most of the final two months and their lead dipped from 9½ games to 1½ in a span of 16 days with 10 games left.
But the Sox got the last laugh, and they reminded everyone in a zany celebration.
"If you said before the season that we were going to win the division, you're lying," said Konerko, who supported the clutch pitching of Freddy Garcia with his 40th home run in the sixth inning to give the Sox a 4-0 lead.
"I knew we had pitching. If we got any kind of hitting at any time, we were dangerous. People didn't give our pitching any credit. I knew we had a chance."
But the celebration came so suddenly, especially after it looked as if the Sox would have to win at least one game at Cleveland this weekend until the resurgent Indians lost twice to Tampa Bay entering play Thursday.
"I thought it would come down to the last week," said Konerko, who kept the ball from the last out in his locker. "I didn't think we'd blow a 15-game lead or have Cleveland take it away from us. But I thought this division would come down to the last week. I didn't think it would come down to the last week two months ago."
Nevertheless, the Sox had plenty to treasure and enough to look forward to for the playoffs.
Garcia (14-8) continued his mastery in day games (14-3 in his last 21 day starts) by holding the Tigers to two runs in seven innings. "In Seattle, we'd go to playoffs, but I never had a chance to pitch to clinch," Garcia said. "I got the opportunity, and I did it."
Garcia said he made the best of temperatures that dipped into the 50s.
"I wasn't sweating," Garcia said. "My first pitch was only 84 m.p.h. I'm the kind of pitcher who finds a way to get away with 84, 85 and make a pitch."
The Sox's much-maligned offense also gave Garcia a cushion. Carl Everett continued his resurgence with his second triple in as many days to give the Sox a 2-0 lead in the first inning.
The Sox also reverted to their small-ball tactics to manufacture a run in the second. A.J. Pierzynski, one of Williams' best off-season acquisitions, led off with a double, moved to third on Juan Uribe's sacrifice and scored on Scott Podsednik's sacrifice fly.