Westbrook entered the game 16 rebounds shy of becoming the first player to average a triple-double for a season more than once. He reached that total with just over nine minutes left in the third quarter and received a standing ovation. He finished with just six points, but had a career-high 20 rebounds and 19 assists.
"I'm very, very thankful and blessed, man, to go out and compete," Westbrook said. "Like I've said many, many times, I don't take this game for granted. I don't take going out on the floor and competing for granted."
George made 13 of 20 shots, including eight of 14 3-pointers.
"I just caught a rhythm early," George said. "It's just sticking with it, staying with the process and just putting work in -- a lot of work in. It paid off tonight."
With a loss, the Thunder would have been a No. 8 seed and forced to play No. 1 seed Houston in the first round. Instead, Oklahoma City will play Utah.
Dillon Brooks scored a career-high 36 points for Memphis.
Westbrook had one of the most unusual first halves of his career to help the Thunder take a 20-point lead. He had 12 assists and 11 rebounds, yet only scored one point and took two shots. George scored 26 points on 9-of-10 shooting, including 5 of 5 on 3-pointers in the first half to help Oklahoma City score a season-high 77 points in the first half.
Brooks scored 16 points in the third quarter to help the Grizzlies trim their deficit to 105-96 at the end of the third quarter. The Grizzlies scored 39 points in the period.
Memphis hung tough in the fourth quarter before back-to-back 3-pointers by Terrance Ferguson and George pushed Oklahoma City's lead to 133-116.
"Obviously, I thought we had plays where we could have prevented points, but for the most part, they (Memphis) just played really well tonight," George said. "I thought we did a great job of not falling into just being complacent. I thought we played phenomenal tonight. It just so happened that they played well as well. It's like that sometimes. It's just great that we played well enough to win."
Grizzlies: Marc Gasol (rest), Tyreke Evans (personal reasons), JaMychal Green (knee soreness), Wayne Selden Jr. (right knee soreness), Andrew Harrison (right wrist/left shoulder) and Jarell Martin (left ankle) all sat out.
Thunder: Westbrook brought F Nick Collison out to midcourt with him before the game. Westbrook said he wasn't sure if it would be the 37-year-old Collison's last regular-season game, but he wanted the crowd to acknowledge Collison's contribution to the franchise. ... G Alex Abrines (concussion protocol) did not play. ... Westbrook had seven assists in the first quarter. ... Brewer was fouled on a 3-pointer in the fourth quarter and left the game for good with a knee sprain.
Westbrook matched a season low with two field goals made and set a season low with nine field goal attempts.
Westbrook didn't shoot well, but the other four starters shot a combined 33 for 55 from the field.
Bickerstaff on the team's 22-60 finish: "When you go through these types of times, everybody who is involved's true character comes out. It's easy when things are roses and sunshine to be a good player, a good teammate, to be a positive coach, whatever it may be. But these times, who are you? Hopefully everybody involved learned from it."
Grizzlies: Season is over.
Thunder: Will open the playoffs this weekend.
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