BOSTON, March 10 (Ticker) -- Vitaly Potapenko held onto the ball and the Boston Celtics held onto the lead.

Potapenko grabbed three key rebounds in the final 90 seconds to help the Celtics hang on for a 98-91 victory over the Washington Wizards and move into a tie for third place in the Eastern Conference.

Often a forgotten man in Boston's offense, Potapenko showed the importance of his role. He pulled down a pair of offensive rebounds on an extended possession that led to Paul Pierce's two free throws, giving Boston a 95-90 lead with 53 seconds to play.

"That was the play of the game right there," Pierce said. "The two offensive rebounds that took a minute off the clock and we got a bucket." "Offensive rebounds toward the end of the game really was in our favor," Celtics guard Tony Delk said. "We got another chance to get off one more shots and run time off the clock."

NBA TV highlights from Wizards-Celtics: 56k | 300k Antoine Walker slams home two of his game-high 23 points. Noren Trotman NBAE/Getty Images

The Wizards outrebounded the Celtics, 44-32, and limited them to nine on the offensive end. But two came on that possession.

"That occurred because we were trying to help in the post," said Wizards coach Doug Collins.

"That exchange was big," Wizards forward Christian Laettner added. "It would have been nice to get those and see what happened."

Laettner and Boston's Antoine Walker each made a foul shot and the Wizards took possession with 33 seconds remaining. Tyronn Lue missed a shot and Potapenko hauled in the rebound. He drew a foul and his two free throws sealed the win.

Walker scored 23 points and Pierce added 18 for Boston (35-27), which caught slumping Milwaukee for third place in the East.

"It's not necessarily to catch up to the Bucks or catch up to Detroit as much as it is to try to catch up to New Jersey (in the Atlantic Division)," O'Brien said. "It's important for us to just focus on the daily task, which is if you get wins, you can't really worry about the other people that aren't playing against you that night."

In 26 minutes, Potapenko had nine points and eight rebounds. He took just two shots, making one, and was 7-of-8 from the line.

"Two really huge rebounds by Vitaly really may have been the game," O'Brien said.

Richard Hamilton scored 21 points and Lue added 19 for the Wizards, whose third straight loss took a familiar pattern. Without superstar Michael Jordan, Washington has played tough but has failed to execute down the stretch.

"We have not been able to finish. You saw it again today," Collins said. "This is a carbon copy of the losses that we've had in the last four or five games. Under pressure, we take bad shots, make bad decisions on both ends of the floor and teams have capitalized on that."

In a ragged game, neither team led by more than seven points. There were nine ties and 14 lead changes, the last one on a dunk by Pierce that closed the third quarter.

Pierce and Walker made 3-pointers and Eric Williams sank a pair of free throws to extend the lead to 84-77 with 7:45 to go. The Wizards fought back and a 3-pointer by Chris Whitney made it 91-88 with 3:11 remaining. Walker answered with two free throws.

"I'm not surprised we came out with a win," Pierce said. "It wasn't a pretty game, but some way we grinded it out and we won it in the fourth quarter."

Kenny Anderson scored 17 points, Rodney Rogers added 13 and Delk 12 for the Celtics, who shot 42 percent (33-of-78), including just 6-of-25 from 3-point range. But Boston committed only nine turnovers.

Courtney Alexander scored 15 points and Laettner pulled down a season-high 16 rebounds for the Wizards, who shot 45 percent (33-of-74) but committed 21 turnovers.