This was a case of a younger player being unwilling to take any more guff from a veteran.
With a little over eight minutes remaining in the second quarter and New Orleans leading 32-31, Rivers shoved Collison as the Thunder big man tried to set a pick on him. The extracurricular activities continued as the action moved to the other end, with the 6-foot-9 Collison veering into the 6-foot-4 Rivers from behind as they ran up the court.
Rivers immediately took exception to the shove from behind, making a beeline for Collison and hugging him with both arms in the paint. Collison responded by wrapping up Rivers' head, and the two engaged in a staredown before they were quickly separated.
Both players were ejected after receiving technical fouls. Rivers departed with eight points (on 2-for-4 shooting) and two assists in 14 minutes. Collison left with zero points (on 0-for-2 shooting), two assists and one rebounds in eight minutes.
Tyreke Evans led the Pelicans to the surprise victory with 41 points (on 14-for-26 shooting), nine rebounds, eight assists and three steals.
New Orleans improved to 33-48 with the win. Oklahoma City dropped to 58-23 with the loss. The defeat complicates things slightly for the Thunder, who now still have some work to do to hold off the Clippers for the West's No. 2 seed. Oklahoma City can drop to the West's No. 3 spot if the Thunder lose to the Pistons on Wednesday and the Clippers win both of their remaining games against the Nuggets and Blazers.