Al Horford had 19 points and 11 rebounds in his second game back from a pectoral injury as host Atlanta remained alive in its Eastern Conference first-round series with Boston.

Jeff Teague added 16 points and Josh Smith had 16 rebounds to go with 13 points as the Hawks cut Boston’s lead in the best-of-seven to 3-2.

Paul Pierce and Kevin Garnett scored 16 points and Ray Allen added 15 for the Celtics.

Game 6 is Thursday in Boston.

Horford hit back-to-back baskets to snap an 83-83 tie and give the Hawks the lead for good. Pierce hit a 3-pointer with 50.6 seconds left and Boston had a chance for a game-winning shot after Rajon Rondo recorded his fifth steal of the contest.

Rondo anticipated Smith’s inbounds pass with 10.9 seconds left, but fumbled the ball in the frontcourt in the final seconds and the Celtics were unable to get off a shot.

Atlanta used a 10-3 run to take an 83-76 lead on Joe Johnson’s basket with 4:19 remaining. Boston responded with seven straight points and tied the game on Allen’s 3-pointer with 2:41 left.

The Hawks opened up a 12-point third quarter lead by scoring 10 consecutive points. Johnson started the run with an 18-footer and Horford scored the final three points on free throws.

Boston quickly answered the surge with 10 points of its own. Rondo scored six points and Mickael Pietrus scored on a reverse layup to pull the Celtics within 66-64 in the final seconds of the quarter.

Johnson and Marvin Williams added 15 points apiece for Atlanta.

Brandon Bass scored 14 points and Rondo had 13 points and 12 assists for Boston.

GAME NOTEBOOK: Williams had three of Atlanta’s seven 3-pointers. … Boston had 11 steals. … Smith missed his first eight field-goal attempts and was 1 for 9 in the first half. … Rondo committed five of Boston’s 14 turnovers.