The Bucks dropped their regular season finale 127-116 to the Oklahoma City Thunder.
Oklahoma City played without injured Paul George, but Westbrook, Jerami Grant and Dennis Schroder led a hot-shooting effort from 3-point range. Westbrook tallied his 34th triple-double of the season with 15 points, 11 rebounds, and 17 assists.
The Bucks had already clinched the No. 1 seed in the Eastern Conference and rested star Giannis Antetokounmpo and some other key players. They finish the regular season 60-22, 33-8 at home.
Khris Middleton was the only usual Bucks starter in the starting five, and he scored 21 points in 17 minutes. He took an intentional foul with 5:32 left in the third quarter to end his night, moments after scoring to bring Milwaukee within 84-79.
Tim Frazier scored a career-high 29 points for Milwaukee (60-22) and D.J. Wilson added a career-high 18 while grabbing 17 rebounds. Rookie Bonzie Colson started and scored 21 points.
The Bucks will face the Pistons in the first round of the NBA Playoffs. Milwaukee swept all four meetings with the Pistons this season. The playoffs begin this weekend, with dates and times to be announced.