The Warriors pulled to 95-94 on a 3-point play by Rod Higgins, but Chapman made a 15-footer with 6.5 seconds left.
The Warriors, who have the league's worst record (6-27), were led by Rod Higgins's 16 points.
A fifth 3-pointer, this time by Rod Higgins, gave the Kings an 87-86 lead with six minutes to play.
They were led by Terry Teagle and Rod Higgins with 14 points apiece.
The Warriors also got 25 points off the bench from Rod Higgins.
Rod Higgins hit two free throws with 52 seconds remaining, giving the Warriors a 98-96 lead.
Rod Higgins tied the score at 104-104 on a free throw with 22 seconds left.
Rod Higgins hit two successive 3-pointers to give the Warriors their first lead at 101-100 with 2:22 left.
Rod Higgins, a Warrior forward, said the announcement was unexpected.
Replaced Rod Higgins, forward, on their roster.