The Caltex Socceroos midfielder has played a crucial role in Huddersfield Town's dramatic penalty shoot-out win over Sheffield Wednesday in the Championship playoffs, after the scores were locked at 1-1 after extra-time.
Ahead 3-2 after three penalties each, Mooy stepped up to calmly slot Town's fourth spot-kick, but had to endure an agonising wait as team-mate Jack Payne saw his penalty beaten away.
But Huddersfield goalkeeper Danny Ward saved Wednesday's fifth attempt, sending his team-mates and the visiting fans into raptures.
The tie was poised at 0-0 after a goal-less first leg and it was Sheffield Wednesday who took the lead at Hillsborough when Stephen Fletcher headed in just after half-time.
But with 17 minutes remaining, Huddersfield substitute Collin Quaner crossed from the right and Nahki Wells' close range effort was deflected into his own net by Wednesday defender Tom Lees.
There was no further scoring in normal time or added time, or in 30 minutes of extra-time, leading to the dreaded penalty shoot-out.
Huddersfield will now meet Reading at Wembley on May 29 for a place in the 2017/18 Premier League.
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