The defeat leaves the longtime league leaders three points adrift with four games remaining.
The result puts pressure back on Liverpool and Manchester City.
Central Coast’s final game has been officially reschedule.
United with meet bitter rivals Manchester City in the final.
The holders will defend the FA Cup at Wembley.
Their regular season rivals have been waylaid by Middle East weather conditions.
Captain Alex Rufer couldn't convert a 96th-minute spot kick, putting Central Coast Mariners in the box seat.
The result sees them back atop the competition table with one game left in the regular season.
Zawada was expected to miss the rest of the season because of a thigh injury he suffered in February.