Westbrook missed his first eight shots and 12 of his first 13 before finding a rhythm, but the Lakers didn't wilt down the stretch.
"The thought the execution at the end of the game by our team definitely could have been better," Oklahoma City coach Scott Brooks said. "It's something that we're pretty good at, but a lot of that had to do with their team. They're a physical team, and they were moving us around a little bit towards the end."
Los Angeles took the lead with 6:15 to play on a jumper by Metta World Peace, who had 15 points and 10 rebounds. The Lakers nursed a small advantage in the final minutes, going up 101-95 on Gasol's driving layup with 1:09 to play.
Bryant then hit a tough 19-foot jumper with 37 seconds left, and Westbrook couldn't answer. Durant didn't have a field goal in the final 6:39, scoring just seven points in the fourth quarter of Oklahoma City's third loss in 11 games.
Oklahoma City routed the Lakers earlier this month, with Durant scoring 42 points and Westbrook adding 27 while Los Angeles played without Howard and Gasol.
Howard had just eight points and 10 rebounds this time out while fighting foul trouble and missing eight of his 10 free throws. Bryant and Nash led a passionate effort by the Lakers, whose season-long missteps and embarrassments have left them well out of the playoff picture heading into the second half of the season.
"I'm very excited to see our progress," Howard said. "We're going to continue to work, continue to talk to each other. The biggest difference is we're holding each other accountable for everything. We had a great talk in Memphis, and it's carried over."
NOTES: The clubs conclude their season series in Oklahoma City on March 5. ... Lakers owner Jerry Buss celebrated his 79th birthday. The Basketball Hall of Famer hasn't attended a game this season while dealing with health concerns. ... Derek Fisher, the five-time champion Lakers guard who finished last season with the Thunder, watched from a courtside seat. Denzel Washington, Jay-Z, Alessandro Nivola, Horace Grant and baseball stars Matt Kemp, Vernon Wells and Michael Young also sat courtside.