Behind double-doubles and stifling defense late from Kevin Garnett, Paul Pierce and Rajon Rondo, the Boston Celtics defeated the Washington Wizards in overtime, 100-94, at TD Garden to complete a home- and-home sweep.

Garnett, who tallied 20 points, 13 rebounds, two blocks and a steal, grabbed a huge board off a Chris Singleton miss in overtime and outletted to Rondo, who found Brandon Bass underneath the basket for an uncontested dunk to all but seal the victory.

Rondo posted his fourth-straight double-double with 18 points and 14 assists, while Pierce totaled 15 points and 10 rebounds for the Celtics, who have beaten the Wizards in the last six meetings.

Martell Webster and Kevin Seraphin scored 16 points apiece for the Wizards, but each had costly turnovers late in the fourth quarter.

"We gotta learn to play down the stretch of games," said Washington coach Randy Whittman.

Rookie Bradley Beal also contributed 16 points in the loss for the Wizards, who are still in search of their first win through three games.

Down 83-82 following a Beal three, Garnett stole the ball from Seraphin, who then fouled him with Washington in the penalty. The players appeared to get tangled up on the play, and Garnett was called for a technical foul.

Webster knocked down the free throw for Washington, but Garnett converted both of his attempts to tie the game at 84-84 with 1:08 to play.

Garnett blanketed Seraphin again on the next Wizards' possession, but this time Pierce snuck in and stole the ball from the forward. Seraphin again committed a foul to send Pierce to the line, but he only made 1-of-2.

Pierce made up for the missed attempt, however, when he came up with another steal, this time stripping Webster of the ball.

Webster grabbed Rondo to send him to the line, but he too only converted just 1-of-2 free throws, giving Boston a two-point lead.

Singleton buried two free throws to tie the game after he was fouled by Pierce, but after a Boston timeout, Rondo drained a jumper near the top of the key to give the Celtics the lead back at 88-86 with 26 seconds left.

Singleton again tied the game for Washington when he penetrated the lane on the following possession and threw down a ferocious dunk.

The Celtics called timeout again to advance the ball to halfcourt with 9.4 seconds remaining, but Rondo's three missed as time expired, sending the game to overtime.

"You knew coming into this night, no matter who you're playing, when you're play a team back-to-back games, you give them three days, you knew it'd be a tough game," said Celtics coach Doc Rivers. "But we made it so much harder."

Boston did not have much difficulty in the extra period, as they doubled the Wizards scoring output. Bass scored on a layup to put the Celtics up 95-92 with 1:51 to play in OT and his fast break dunk with 37 seconds to go put the game out of reach.

"We got stops when we needed to," said Rondo. "Overall it's all about the win and that's what we did."

Rondo hit 3-of-4 shots and Garnett pulled down nine rebounds in the first quarter to help set the tone early, as the Celtics took a 21-16 advantage heading into the second.

However, sparked by 21 points from their bench in the second quarter, the Wizards took a 42-37 edge going into halftime.

Jannero Pargo tied the game at 28-28 midway through the second, draining a three for Washington, which went on to take the lead two minutes later following a 3-pointer from Webster. The Wizards led by as many as seven after Singleton scored on a layup with 1:47 remaining.

Following a pair of Pierce free throws, the Celtics took a one-point lead with 5:17 to go in the third. From six feet behind the arc, A.J. Price buried a 3-pointer to give the Wizards the lead back, but the Celtics created some separation shortly thereafter.

Boston closed out the third on a 12-0 run, which was bookended by a pair of Jason Terry jump shots to give the Celtics a 66-58 lead. Chris Wilcox, who completed a three-point play after being fouled on a layup, scored five during the stretch.

Price and Seraphin scored baskets on consecutive possessions with 3:36 left in the fourth to tie the game and Washington grabbed the lead less than two minutes later when Beal drained a long three to put the Wizards ahead 83-82.

Game Notes

Rondo extended his streak to 28 straight games with at least 10 assists ... Webster hit 3-of-6 from three-point range. He needs just one more to reach 500 for his career ... There were 39 combined turnovers in the game. Washington had 20.