Kyrie Irving scored 12 of Boston’s last 17 points and finished with 28 to help the Celtics remain in sole possession of the Eastern Conference lead with a 110-104 overtime victory over the Washington Wizards on Thursday night.

Jaylen Brown added five of his 18 points in overtime for Boston. The Celtics have won five of six, and remained a game ahead of Toronto in the race for the East’s top playoff seed after the Raptors win over New York earlier Thursday.

Otto Porter had 27 points and 11 rebounds for Washington, and Bradley Beal had 18 points and matched his career high with nine assists.

But as John Wall remains sidelined following knee surgery, the Wizards committed 22 turnovers and shot just 2 for 12 in the overtime period, dropping their second straight game after winning five straight.

Irving went 9 of 10 from the foul line in his second game back from a thigh injury. And after Boston allowed Washington to come back from a 10-point fourth-quarter deficit, he tied it from the line in the late seconds on three made foul shots after luring Markieff Morris into a foul on a 3- point attempt.

That was part of 10 straight points for Irving before finding Brown for a layup that made it 105-103 with 2:32 left in overtime.

Brown stretched the lead to five when he hit a contested baseline 3- pointer about a minute later, and the Wizards failed to get within a possession after that.

TIP-INS — Celtics: Signed and activated free-agent C Greg Monroe, but did not make a trade at the NBA trade deadline. … Coach Brad Stevens wasn’t surprised. “It was probably the least amount of time that I was paying attention to it or on the phone over these days in five years,” he said. … Monroe was one of three Celtics players to receive a technical foul in separate incidents, along with F Marcus Morris and G Terry Rozier

Wizards: Traded G/ F Sheldon Mac to the Atlanta Hawks for a 2019 second-round pick in a move coach Scott Brooks said gave Washington the flexibility to sign one or two players. “We’re definitely looking,” Brooks said. … Mac (torn Achilles), who was then waived by Atlanta, has not played this season. … F Kelly Oubre received a technical foul in the fourth quarter.

NOT TAKING THE BAIT — Although the Wizards won their first five games after losing G John Wall to knee surgery, Brooks denied the notion his absence has been a positive.

“ He knows how I feel about him,” Brooks said. “He knows how the organization, his teammates feel about him.”