Kevin Durant scored half of his 36 points in the fourth quarter and the Thunder got some unexpected offense from Serge Ibaka to beat the Spurs, 109-103, tying the Western Conference finals after four games.
The 6-foot-10 Ibaka, known more for his defense, had 26 points and made all 11 of his field goal attempts.
Durant, who went 7-of-9 from the floor in the final quarter, scored 16 straight points for his team at one point to keep the San Antonio at bay after the visitors trimmed the deficit to four midway through the period.
Oklahoma City, which moved to 7-0 at home this postseason, also received 15 points and nine boards from Kendrick Perkins, but Russell Westbrook was limited to seven points on 2-of-10 shooting.
"He opened up the defense by making passes. That's what our guys did tonight, finding the bigs for open shots," Thunder coach Scott Brooks said of Durant. "Serge and Perk had an offensive night that we're certainly all happy with."
The Spurs won 10 consecutive playoff games before losing on Thursday. Now they had back to San Antonio for Game 5 Monday trying to just maintain homecourt advantage.
Tim Duncan had 21 points and eight rebounds for the Spurs, who also received 17 points from Kawhi Leonard, 13 from Manu Ginobili and 12 from Tony Parker and Boris Diaw.
Stephen Jackson's driving layup cut the margin to 90-86 with 5 1/2 minutes left, but Durant converted a three-point play and with under three minutes left accounted for the basket that took the wind out of San Antonio's sails.
James Harden, who finished with 11 points, seven boards and seven assists, threw a pass to a cutting Durant. He finished the alley-oop jam and was fouled by Jackson. The three-point play moved the difference to 100-90 with 2:48 left, and the Spurs never got closer than six the rest of the way.
Durant finally ended his 16-point scoring binge with a jumper with 1:32 left, moving the lead to 102-93.
"I didn't tell myself that I need to go score, because what we were doing was working," Durant said. "We were passing the ball and guys were making shots. They went on a little run there. So I just wanted to stick with what we were doing. It started to open up for me, and I saw some lane that's gave me some opportunities to make some shots."
San Antonio had a stretch of 20 straight victories until Thursday's 20-point loss, but head home with history on its side. Oklahoma City is trying to become the 15th team in NBA history to overcome a 2-0 deficit in a best-of- seven series. The Spurs were the last team to do it when they came back to defeat the New Orleans Hornets in the 2008 Western Conference Semifinals after trailing 2-0.
"Both teams took care of business at home. Hopefully we continue that trend," Ginobili said.
Perkins scored nine in the opening quarter, helping the Thunder overcome an early eight-point hole and forge a 26-26 tie after 12 minutes. Thabo Sefolosha's dunk provided the final points of the period.
An 11-2 Thunder run in the second opened a 43-33 lead with under five minutes left. Ibaka seemed to be all over the court, and his jumper with 3:23 left had the difference at nine.
Durant's right elbow jumper with 6.6 seconds left moved the lead to 55-43, and Leonard then hit one from beyond the arc, but a video review showed the ball left his hand just after the red light went on.
Ibaka's jumper with 5 1/2 minutes left in the third gave the Thunder their largest lead at 68-53, but the Spurs rallied with an 18-2 run, speared by Ginobili. His three made it a 73-71 contest with 1:16 left.
The defensive play of the night came from Ibaka in the closing minute. DeJuan Blair rolled to the basket for what seemed like an easy fastbreak dunk, but Ibaka raced in from behind and swatted the ball away, keeping it a 75-71 game moving to the fourth.
Even when Ibaka didn't have the ball, he was opening shooting lanes for his teammates or rolling to the basket for second-chance opportunities. His screen on Leonard opened Harden for a three from the left wing for an 84-76 difference. Under two minutes later, Ibaka powered to the basket to tip in Harden's missed shot.
"Serge continuously knocked those shots down in the first three quarters," Westbrook said. "Then when it was time for Kevin to iso and give us what he needs, he has a lot of space. That just shows the commitment that we're making the right play, and it worked for us."
Prior to Saturday, Ibaka's career-high in the regular season or playoffs was 22 points...The Thunder shot 56.4 percent, while the Spurs made half of their 82 field goal attempts...Durant also had eight of his team's 27 assists.