Pierce scored 23 points while Rondo added 15 points and 15 assists as the Celtics evened the best-of-seven Eastern Conference final at 2-2 with game five on Tuesday at Miami and game six back in Boston on Thursday.
Either the Heat or the Celtics will face the Western Conference champions, the San Antonio Spurs or Oklahoma City Thunder, in the NBA Finals starting on June 12.
After regulation time ended deadlocked at 89-89, stars became spectators as Pierce fouled out, collecting his sixth violation 38 seconds into over-time to foul out for the third time in five playoff games.
“When your leading scorer goes out, you have got to step up and make plays,” Rondo said. “That’s what we did.”
Miami’s LeBron James, who scored a game-high 29 points, fouled out with 1:51 remaining, the first time he had fouled out since leaving the Cleveland Cavaliers and joining the Heat two years ago.
“It was like chess. They took our queen and we took their queen,” Celtics guard Ray Allen said. “All that has to happen is the game has to be won. It doesn’t matter what it looks like.”