Thunder's Harden undergoes tests after concussion
Harden participated in limited activities on Monday but must go through additional steps under the NBA's concussion policy before he is cleared to play again.
Harden dropped to the ground after taking a vicious backward elbow to the head from Metta World Peace after the Lakers' forward had dunked over two Thunder players late in the second quarter of Los Angeles' double-overtime win Sunday.
World Peace, who claims he accidentally clipped Harden while celebrating the dunk, faces discipline from the NBA as the regular season winds down and the Lakers prepare to open the playoffs this weekend.
Copyright 2012 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.