BOSTON -- Oklahoma City Thunder guard Russell Westbrook said there was no one to blame but himself for his turnover in the final seconds of the Thunder's 134-129 loss to the Boston Celtics on Sunday afternoon.

"In a late game like that, I've just got to take care of the ball," Westbrook said. "That's on me."

Westbrook's gaffe came with a little more than 10 seconds remaining and the Thunder trailing by two. When Jayson Tatum was fouled and sent to the free throw line with 16.2 seconds left, following a made 3-pointer by Thunder forward Jerami Grant to cut Boston's lead to 130-129, the plan was for Westbrook to try to get the ball upcourt and attack if Tatum missed one of the two free throws.

After making the first free throw, Tatum did just that, and Westbrook, who finished with 22 points, 12 rebounds and 16 assists for his 19th triple-double of the season (and sixth in a row) wound up with the rebound, allowing him to attack Boston's defense while it wasn't set, precisely as coach Billy Donovan had hoped.

"I talked to him before the two free throws and talked about if there was a miss to get him to get it and go quickly, save the timeout," Donovan said. "It was a great opportunity. There was a missed shot, everybody was at the free throw line, and we've got the fastest guy in the league."

As Westbrook came down the left side of the court, he put the ball behind his back as Kyrie Irving tried to reach in for a steal. Then, as Tatum did the same, he brought the ball back to his left -- only to lose control of it.

He tried to regather it and tip the ball out to Dennis Schroder, who was open in the corner, but Al Horford grabbed the ball instead. After it wound up in Tatum's hands and he was fouled with 7.4 seconds left, he made both free throws to put Boston up by four, and the game out of reach.

"That was the plan," Westbrook said. "That was the plan. Just a turnover."

"I'm sure Russell would like to have the play back," Donovan said, "but I like what we tried to do because if he doesn't get all the way to the rim, or he doesn't turn it over, we're probably going to wind up with an open 3 or a pretty good look from the perimeter."

Westbrook got one more chance when, after being fouled on a shot attempt with 5.2 seconds remaining, he hit the first free throw to move Oklahoma City to within three before attempting to intentionally miss the second.

When he did, though, he failed to hit the rim, which meant the ball went back to the Celtics. Once Boston inbounded the ball, Marcus Smart was fouled and made two free throws to ice the game.