Memphis, TN (Sports Network) - Paul Pierce scored 28 points, as the hot- shooting Boston Celtics controlled overtime to take a 116-110 win over the Memphis Grizzlies. Kevin Garnett had 18 points and nine rebounds for the Celtics, who shot 57.7 percent -- including 7-of-12 from three-point range. Rajon Rondo ended with 17 assists and 11 points. Shaquille O'Neal added 18 points and six rebounds in a little more than 22 minutes to help Boston win for the eighth time in its first 10 games. Rudy Gay's 22 points and Zach Randolph's 21 paced Memphis, which has dropped its last two. Gay connected on two jumpers within the final 46.3 seconds in regulation to tie the game at 99-99, and Boston had one last possession with 7.3 to go. Pierce had the ball, but wasn't able to get a shot off in time, and the game went to the extra period. Glen Davis opened overtime with a jumper, keying a seven-point burst that Rondo capped with a basket with 2:07 remaining. In that same span, Memphis missed four shots. Garnett got a jumper to fall with 1:36 left for a 108-101 lead, and moments later Randolph missed a turnaround. But in battling for the rebound, Randolph yanked Garnett to the floor by the shoulder. Randolph continued to stand by the fallen Garnett and appeared incredulous when Rondo came over to pull him away. Nothing more serious happened, but Randolph earned a flagrant foul-1 on the play, leading to two Garnett free throws and a 110-101 game with 59.4 seconds left. The Celtics secured the win at the foul line. The game was tied, 27-27, after a tight first quarter, but Boston ran off nine consecutive points shortly into the second. Nate Robinson ended the rally with a layup for a 36-29 advantage with 8:40 to play. Garnett's jumper late in the half expanded Boston's lead to a game-high 11, but Memphis scored the final six points of the quarter to get within 54-49 at the break. The Grizzlies then scored the final five points of the third quarter to make it 73-73 going to the fourth. It was mostly a one-possession game down the stretch, but Ray Allen's bucket with 55.0 on the clock had Boston ahead 99-95. Robinson and Allen each finished with 15 points for the Celtics...Memphis shot 53 percent overall, but just 2-of-9 from three-point range...The Grizzlies held a 38-32 rebounding edge. Randolph had 11 boards...Boston ended its road trip with a 3-1 mark, and hosts Washington on Wednesday...Memphis plays at Orlando on Monday.