Phil Collins suffered a "severe gash on his head close to his eye" ... forcing the cancellation of his final 2 shows in London.
The singer says he took the nasty spill in his hotel room while walking to the bathroom in the middle of the night. He hit his head on a chair. Phil needed stitches and he's being kept under observation at a hospital.
He suffers "drop foot" as a result of a previous back surgery, and now has trouble walking sometimes
His June 8 and 9 shows at Royal Albert Hall have been postponed to November. He offered "sincere apologies" to his fans.