Celtics 83, Hawks 80: Kevin Garnett hit the go-ahead basket with 30.4 seconds left to cap off an epic individual performance as host Boston defeated Atlanta to win the Eastern Conference first-round series in six games.

Garnett had 28 points, 14 rebounds and five blocked shots as the Celtics advance to play the Philadelphia 76ers in the second round.

Paul Pierce scored 18 points and Rajon Rondo added 14 for Boston.

Josh Smith scored 18 points, Joe Johnson had 17, Marvin Williams tallied 16 and Al Horford added 15 points for Atlanta.

Garnett’s basket gave Boston an 80-79 lead and Ray Allen hit one of two free throws with 9.3 seconds left. Horford was fouled with 2.3 seconds left and missed the first free throw before sinking the second.

Pierce hit two free throws with 1.3 seconds left and Atlanta couldn’t get off a final shot.

The Hawks trailed by nine early in the fourth quarter but recovered to take a 79-76 lead with 2:23 to play as part of a 14-2 run. Smith scored the go-ahead dunk with 3:12 to play and Horford had eight points during the surge.

Rondo finished the third quarter with a flourish by hitting a buzzer-beating jumper to give Boston a 67-63 lead. Garnett scored six points during a 7-0 fourth-quarter run as Boston took a 74-65 lead with 8:41 to play.

Atlanta led 31-25 early in the second quarter before Boston went on a 16-0 run to open up a 10-point lead. Garnett and Pierce each had five points during the surge, which culminated on Rondo’s layup with 3:51 left in the half. The Celtics led 47-41 at halftime.

GAME NOTEBOOK: Garnett posted four double-doubles in the series. … Williams made four of Atlanta’s seven 3-pointers. … Celtics guard Ray Allen was just 1 of 7 from the field … The Hawks committed 13 turnovers – seven by Horford.