Paul Pierce had a triple-double and the Celtics edged the Indiana Pacers 99-88 at Boston Sunday for their 13th straight win.

Pierce was one of three Celtics to finish the game with a team-high 18 points. He also had 10 rebounds, 12 assists and four steals.

The Celtics led most of the way but were sloppy throughout and unable to put the game away until the final stages.

James Posey hit a 3-pointer early in the fourth quarter to cut Boston's lead to 71-70 but the Celtics responded with a 10-2 run. Pierce had six points in the run as Boston took an 81-72 lead with 7:33 to play. Indiana never got closer than four points the rest of the way.

Boston (22-4) led 51-48 at the half.

Nate Robinson, playing for the injured Rajon Rondo, had 18 points as did Glen Davis.

Shaquille O’Neal returned to the Boston lineup after missing the past four games with a sore left calf. O’Neal scored 11 points and grabbed five rebounds.

The Pacers (12-14) were led by Danny Granger with 19 points. Indiana attempted 96 field goals in the games shooting 37 percent.