The American second seed was still on court well past midnight and, on her least favorite clay-court surface, was sent packing 6-2 2-6 6-1 by Swiss Patty Schnyder.
Sharapova won a tight first set and then hurried along in the second, leaving Djokovic and his opponent, Sam Querrey, to take the court after midnight.
At a dramatic midnight conclave, the country's Supreme Court judges gave credence to rumours that Mr Zardari planned to sack them and vowed to defy him.