Daequan Cook proved to be the perfect substitute for the NBA's top-scoring bench player.
Durant scored 32 points and Cook had all 19 of his points in the fourth quarter to rally the Thunder to a 118-110 win against the Sacramento Kings on Tuesday night in their first game since Harden took an elbow to the head.
Harden wasn't able to pass league-mandated tests to allow him to return after the concussion he suffered when he was hit by the Los Angeles Lakers' Metta World Peace, formerly known as Ron Artest.
Cook broke out of a slump to help ease that pain, at least for one game.
"He's a big factor on our bench. Not just our bench but our whole team," Cook said. "The bench guys had to step up big."
Cook started the fourth quarter with a jumper and a 3-pointer to erase a four-point deficit, and he went on to score Oklahoma City's first 14 points of the period and put the Thunder ahead for the first time since the first quarter.
"Fortunately with James out, Daequan was that guy," Durant said. "He was able come through for us and make some really big shots."
The performance by Cook and the other backups was enough to convince coach Scott Brooks to leave his starters on the sideline in a game without much on the line.
The Thunder are locked into the No. 2 seed in the Western Conference playoffs but did ensure that they'll finish ahead of Miami -- the No. 2 team in the East -- and would have home-court advantage if that star-studded NBA finals materializes.
DeMarcus Cousins led Sacramento with 32 points after finding out about 3 hours before game time that the league had rescinded his 13th technical foul and he wouldn't have to serve a one-game suspension.
Travis Outlaw moved into the starting lineup and scored a season-high 20 points, surpassing 10 for only the fourth time this season. Jason Thompson scored 22, Tyreke Evans had 18 and Isaiah Thomas 11 as all five Sacramento starters hit double figures.
The youthful Kings will try to avoid finishing the season with the West's worst record when they host the Lakers on Thursday night.
"You can see upside but it's not much that you want to talk about," Thompson said. "You want to be about it."
Durant extended his lead in a tight NBA scoring race with the Lakers' Kobe Bryant despite sitting out the entire fourth quarter. Durant, who moved into the lead Sunday, is averaging 27.97 points per game to Bryant's 27.86 with each having one game left.
"Hopefully it's a fun one. That's what the fans want to see, I guess," Durant said. "But for me as a player, all I'm worried about is getting better."
Bryant will get the last chance to move ahead, playing a night after Oklahoma City's regular-season finale Wednesday night against Denver.
"I don't care about that," Bryant said. "If I did, I would have went for 50 (last week) in San Antonio. They were playing me straight-up in single coverage."
Sacramento made 18 of its 22 shots (82 per cent) in the first quarter and then scored 10 of the first 12 points in the second to go up 50-37. Oklahoma City closed to within 59-57 by halftime, only to give up a 10-0 run in the third that pushed the lead back out to 13.
Royal Ivey put Oklahoma City ahead to stay with a long jumper from the left side with 3 minutes left, and Cook's 3-pointer in transition extended the lead to 114-107 with 44.9 seconds left. Cole Aldrich hit all four of his free throws to close it out.
Cook had made only 11 of 37 shots (30 per cent) since returning from a sprained right knee earlier this month.
"DC is a terrific shooter but he has to continue to believe in that shot and keep shooting it," Brooks said. "I thought the last five or six games when he missed a shot, he kind of got down on himself and was concerned about the next one. If you do that, you can never make the next shot."
Cook said he still wasn't completely healthy and then was asked what percentage he's playing at right now.
"I couldn't tell you," he said. "But after tonight, I feel a little better."
NOTES: Sacramento's first-quarter shooting barrage was the fourth-best in the NBA this season, according to STATS LLC. Indiana went 14 for 16 (88 per cent) in the first quarter against Washington on April 4. Denver shot 84 per cent against Detroit on March 21 and Miami shot 82 per cent against Milwaukee on Feb. 1. ... The Kings haven't won consecutive games since a three-game streak ended on March 20. ... Oklahoma City is 3-0 without Harden, who averages 16.8 points -- tops among NBA reserves.