BOSTON — After a record-setting seven overtimes in the first six games, the defending NBA champion Boston Celtics made an early night of it with a dominating stretch in the second.

That's second quarter, not second OT.

Ray Allen followed his 51-point Game 6 performance with 23 last night, Paul Pierce added 20 and Boston pulled away from Chicago just before the half to finish the Bulls off, 109-99 — a rare regulation victory in what might have been be the best first-round playoff series in league history.

"I don't see great. I just see hard," said Celtics coach Doc Rivers, whose team will play the Orlando Magic in Game 1 of the Eastern Conference semifinals tomorrow. "For a coach, it's just: Win the series."

Ben Gordon scored 33 and Kirk Hinrich scored 14 of his 16 in the fourth quarter to help Chicago cut it to three points — thanks in part to a bizarre scoring change that added a point to the Bulls' score two hours after a first-half 3-pointer was mistakenly ruled a 2.

Boston made all 11 of its free throws in the last 2 minutes to hold on, and the seventh-seeded Bulls return to Chicago knowing they took the defending champs to the limit — and quite often beyond. The four overtime games were a record for a series, and the seven overtimes total were the most any team has ever played in an entire playoff.

"It was a long, grueling series. I thought this was one of the most mentally tough series I've ever been in," Pierce said. "Thank goodness we were battle-tested and we were able to pull this out in seven games. ... We still are the champs until somebody knocks us off."

Kendrick Perkins had 13 rebounds, Rajon Rondo had 11 assists and Eddie House scored 16 points — going 5-for-5 from the floor, including four 3-pointers. Joakim Noah had 15 rebounds for Chicago.

Chicago led by as many as nine points, 32-23, after Gordon scored the first five points of the second quarter — giving him 17 at that point. The Bulls took a 36-30 lead with 8:01 left in the half before Boston scored the next 11 points and 20 of the next 22 to go into the break with a 14-point lead.

After three consecutive overtime games, the series went from Odyssey to oddity when an unusual scoring correction helped the Bulls cut the deficit to three points in the fourth quarter.

Note: With 5:44 left in the game, the public address announcer said that because of a "technical error" Chicago's Ben Gordon was credited with a 2-pointer instead of a 3-pointer, apparently on his basket with 8:32 left in the first quarter. Officials can use video replay to check whether a shot is from beyond the arc or not, but it is supposed to come at the first break after the basket — not three quarters later.