Grizzlies star Zach Randolph went down hard in a painful collision with teammate O.J. Mayo in the first quarter of Memphis' matchup tonight with the Bulls in Chicago. Amateur surgeons online are already claiming an ACL tear and that Z-Bo's season is over, though he later headed to the locker room under his own power. [Comcast SportsNet Chicago]

Update (9:09 ET): CSN is reporting Randolph has a knee contusion (aka a bruise) and will be re-evaluated at halftime.