The New Orleans Pelicans were without six of their top seven scorers, while the Thunder only needed one win to wrap up the No. 2 seed in the Western Conference playoffs.
Monday's contest was set up beautifully for Oklahoma City, but the Thunder fell flat on its face.
Tyreke Evans, the only true scorer remaining in the Pelicans' lineup, dropped 41 points, nine rebounds and eight assists, carrying his flock of Pelicans to an unexpected 101-89 win over the Thunder.
Serge Ibaka led Oklahoma City with 22 points and 16 rebounds, while Kevin Durant added 25 points, seven rebounds and six assists. Caron Butler chipped in 19 points on 6-9 shooting off the Thunder bench.
Reggie Jackson got the start for Russell Westbrook, but played one of his poorer games of the season. Jackson scored just four points on 1-7 shooting and dished out three assists. In fact, Jackson, Thabo Sefolosha and Kendrick Perkins combined for just eight points on 3-17 shooting.
Nick Collison and New Orleans' Austin Rivers were both ejected for a second-quarter altercation. After some pushing and shoving, Rivers appeared to attack Collison, causing both teams to join the skirmish. Although it appeared that Rivers instigated the incident, both players were tossed.
The Thunder shot 40.3 percent from the floor and 28.1 percent from behind the arc. New Orleans shot 44.3 percent and 31 percent. OKC turned the ball over 16 times but forced the Pelicans into just 10.The Thunder was outscored in the paint, 44-32.
With one game remaining, the Thunder (58-23) is still the odds-on favorite to secure the No. 2 seed. A win over the Pistons on Wednesday night at Chesapeake Arena would lock that up. Meanwhile, the gutsy Pelicans (33-48) improved to 21-19 at home.