O'Neal started after sitting out three games with a sprained left knee and had 24 points and seven rebounds, but Gilbert Arenas scored 28 of his 35 points in the second half as the Washington Wizards beat the Pacers 112-96 on Wednesday night.
Washington shot 51 percent from the field, including 53 percent in the second half.
"This is probably going to be my last interview about what we need to do," O'Neal said. "We need to play defense."
The Pacers' last win was on Feb. 21 against Milwaukee. The Pacers can tie their longest-ever losing streak Saturday against Atlanta.
Indiana guard Mike Dunleavy said he's never experienced a losing streak like this.
"When you lose 11 in a row, a losing streak isn't going to end, you've got to snap it," he said. "It's going to take a great effort and a great performance from us. Tonight, Washington played well and they were better than us. Now, we've got to find a way to get out of this thing."
The Pacers were happy with O'Neal's effort.
"It was great to have Jermaine back out there," Indiana coach Rick Carlisle said. "I wasn't sure he was going to play. I thought he played exceptionally well considering he'd been out a week."
"The guy has been banged up the entire time I've been here," Indiana center Troy Murphy said. "For him to come out here, it just shows what kind of player and what kind of man he is."
Danny Granger scored 19 points and Murphy added 17 for the Pacers.
Antawn Jamison scored 27 points and eight rebounds for the Wizards, who had lost their previous three games by a combined six points. The only negative for Washington was that forward Caron Butler left the game early in the second quarter with stiffness in his left knee and did not return.
Arenas continued his run of success against the Pacers. He scored 43 points against Indiana on Feb. 7, 2005, and 40 against the Pacers on Nov. 8, 2006.
Washington led 53-52 early in the third quarter before Arenas scored eight straight points to give Washington a 61-52 lead with 8:23 left in the period. He scored 20 points in the period to give the Wizards an 84-74 lead at the end of the quarter.
"I was able to get to the free-throw line early in the quarter and that helped me with my stroke," Arenas, who shot 7-for-13 from the field in the second half, said. "I couldn't seem to find it in the first half. But once I got to the line like I did, it made me feel comfortable."
Indiana cut the deficit to 88-82 on two free throws by O'Neal early in the fourth quarter, but Washington responded with a 12-2 run to put the game out of reach.
Dunleavy said Arenas was the difference maker.
"The guy made shots," Dunleavy said. "He's tough to guard. In terms of one-on-one players, he's one of the best in the league."
Jamaal Tinsley, who scored a career-high 37 points in a loss to Minnesota on Tuesday, was one of three injured Pacers inactive for the game.
Tinsley was out with a sore left foot and hamstring. Center Jeff Foster (back spasms) and forward Marquis Daniels (sore left knee) were also inactive.
The lack of depth left the Pacers more vulnerable than usual on the defensive end. Washington, one of the league's highest-scoring teams, took advantage.
"We seemed to be able to find our shots any time we wanted to, and we were able to make them," Jamison said. "That is the sign of a team that needed to get a win. I thought we stayed collected and poised against a team that was desperately fighting for a win themselves."
Carlisle said the Pacers are competing well, even though it's not showing up on the scoreboard.
"If anything, I thought at times we tried too hard," Carlisle said. "I think that may have led to some mistakes. The effort is there."
Jamison scored his 12,000th career point in the second quarter. ... Daniels missed his seventh straight game. ... The Pacers had climbed to 29-24 right after the All-Star break. ... O'Neal was called for a technical foul in the third quarter that helped spark a 10-0 Washington run. ... It was Arenas' 24th game with 30 or more points this season.