The Hawks, who overcame a 10-point third-period deficit, outscored Boston, 32-17, in the fourth quarter to beat the East's top seed for the second straight time. Game 5 is scheduled for Wednesday in Boston.

Josh Smith added 28 points, 12 in the fourth period, and had a franchise playoff-record seven blocks. Mike Bibby had 18 points and Al Horford had 13 rebounds for the Hawks, who were 29-of-33 at the foul line.

Ray Allen hit five three-pointers and had 21 points for the Celtics. Kevin Garnett had 20 points, nine rebounds and six steals and Paul Pierce 18 points on an off-night 5-of-14 from the floor.

Rajon Rondo added 14 points and 12 assists.