BOSTON — Face down and knuckles pressed against the parquet floor, Kevin Garnett propped himself up and went back down. Up and down, up and down, he went. And, after eight push-ups, Garnett finally got up on his feet as the raucous crowd at TD Garden erupted with applause.

A home loss on Friday to the Miami Heat would have possibly signified the beginning of the end to the five-year run for the Boston Celtics’ trio of three future Hall of Famers, Rajon Rondo and Doc Rivers.

But the Celtics summoned a 101-91 victory that proved that the old men in green had enough to get back up. Behind Garnett’s infectious energy, Paul Pierce’s timely scoring, Rondo’s all-around floor leadership and Ray Allen showing he still has some hops, the Celtics moved within 2-1 in the Eastern Conference finals.

“My goal was to win. By any means necessary,” Rondo said after scoring 21 points with a game-high 10 assists only two days after an incredible 44-point, 10-assist, eight-rebound game in a Game 2 loss. “We needed to get the win.”

Garnett scored a team-high 24 points and grabbed 11 rebounds and Pierce had 23 points for the Celtics, whose lead grew to 24 points in the fourth quarter when Allen — who has been playing, and struggling, all postseason with bone spurs in his right ankle — drove down the lane for a one-handed dunk.

The Heat made an emphatic run to cut the lead to single digits midway through the period, but the Celtics fended off the run, countering with a Garnett dunk, a Pierce jumper or Rondo layup. Game 4 is Sunday in Boston.

“Everybody knows we’ve been able to bounce back,” Pierce said. “We know we’re capable. We’re not going to lose confidence being down 2-0. You definitely don’t want to get in a situation where you go down 3-1 and they have two games left at home. It doesn’t really figure in your chances.”

The win snapped a five-game playoff winning streak for the Heat, which got little outside of a virtuoso performance from three-time league most valuable player LeBron James, who finished with a game-high 34 points but was limited to just four in the final period.

James came out determined to carry the Heat to a 3-0 series lead, scoring 16 points in the opening period and giving Miami a 28-22 lead when he drilled a 16-foot jumper with 2 minutes 34 seconds left in the first quarter. The Celtics answered by scoring the next 15 points, fueled by suffocating defense, the surprising contributions of reserves Keyon Dooling and Marquis Daniels and the fitness-crazed Garnett.

Dooling started the run with a three-pointer, Daniels made a layup and Dooling had a stunning blocked shot on James that led to a layup on the other end. Garnett then scored the next six points, sandwiching four free throws around a layup. He rose to fight for a rebound and Heat reserve big man Udonis Haslem came over the top of him, knocking him to the ground. Garnett crumpled to the ground and laid there for a few seconds before flipping over for a few push-ups as his teammates stood around him and watched.