PHILADELPHIA

Kevin Garnett yapped his way down the court after big baskets and clearly enjoyed taking it to the 76ers.

Rajon Rondo pushed the ball and relentlessly attacked the lane.

Paul Pierce gutted out a knee injury and grinded his way to the free throw line.

Boston hears the whispers that it’s too weary and too old to win another championship. By the time they forced Sixers fans to flee their seats, the Celtics proved it’s still too early to count them out.

Garnett scored 27 points, grabbed 13 rebounds, and used a dominant second quarter to help the Celtics beat the 76ers 107-91 on Wednesday night and take a 2-1 lead in the Eastern Conference semifinals.

Whistled for a costly illegal pick late in a Game 2 loss, Garnett crushed the Sixers early and never let them think about a fourth-quarter rally.

Garnett scored 13 of Boston’s 32 points in the second quarter and the Celtics became the first team to win by double digits. Game 1 and Game 2 were each decided by one point.

Rondo had 23 points and 14 assists. Pierce, playing with a banged-up knee, had 24 points and 12 rebounds.

Game 4 is Friday in Philadelphia.

That started with making Garnett a focal point.

Garnett had somehow become forgotten in Boston’s offense in Game 2 until the fourth quarter. Coach Doc Rivers said the Celtics simply weren’t going to the 16-year veteran because they had established an offensive presence in the low post.

The Celtics wouldn’t let that happen again.

They needed Garnett at his best in Philadelphia, where the Sixers had won their last four postseason games.

So much for that minor streak. Garnett made 12 of 17 shots and helped the Celtics outrebound the Sixers by 11 on the defensive boards. He buried those 10 to 16 footers with ease in the second quarter to turn a seven-point deficit into a 13- point lead.

Pierce had an MCL injury in his left knee rob him of his jumper and slow him down on both sides of the ball. He scored only 21 points combined in the first two games and failed to be the impact player the Celtics needed if they want to play deeper in the postseason.

All that changed in Game 3. He charged the lane in the first quarter for a couple of angrylooking dunks. He even pounded the backboard for emphasis after one as if to show the Sixers he still had some lift in those legs.

Thaddeus Young scored 22 points and Jrue Holiday had 15 for the Sixers. Lou Williams and Jodie Meeks each scored 13. Starters Elton Brand, Spencer Hawes and Evan Turner combined for only 11 points.

The Sixers hadn’t hosted a second-round game since 2003, when coach Larry Brown and All-Star Allen Iverson ruled the town. Julius Erving walked out to a roaring ovation when he presented the game ball and Eagles quarterback Michael Vick watched from a suite.

The Sixers hoped all the stars and hoopla that helped them knock off top-seeded Chicago would work again.

Back to the drawing board. Young scored three baskets and the rest of the Sixers had only two in the decisive second quarter.

Garnett tortured them from long range, toyed with them from inside, and got some deserved rest on the bench in the final minutes wearing a long-sleeve shirt.

Garnett was whistled for a critical offensive foul late in Game 2 on a potential gametying possession for the Celtics. All seemed forgiven by the time the Celtics raced to a 25-point lead.

Rivers kept Rondo, Pierce and Ray Allen in the game until the final minutes.