Heat coach Pat Riley still isn't ready to test guard Jason Williams' surgically-repaired right knee on back-to-back nights.

Williams did not dress for Friday's game against the Wizards, the first of two games in two nights for the Heat, which plays Memphis tonight at AmericanAirlines Arena.

''I don't think it's as much about pain as it might be stiffness,'' Riley said of Williams, who has played in only 11 of the Heat's 22 after the offseason surgery. ``Until he says he can go back to back, we just want to make sure he's fresh one of those nights.''