The Terriers ended their 45-year absence from England’s top flight courtesy of Christopher Schindler’s penalty in the tense 4-3 shootout victory – after a goalless draw – in front of a crowd of 76,682.
Tipped as favourites for relegation at the start of the season under rookie manager David Wagner, Huddersfield will now play in the Premier League for the first time in their history after clinching a Stg170 million ($293.4 million) windfall.
Mooy, making his 51st appearance of the season, nailed his penalty in between two Danny Ward saves to send Terriers fans wild.
Mooy admitted he had to conquer the negative voices in his head when he stepped up to smash home the penalty in a match described as the richest game in world soccer.
“I just tried to think positive because of lots of negative things come into your head, like if I miss this I’ll cost the team,” Mooy said.
“I didn’t want to be the one who stuffed it up. They creep in but I just try and keep talking positive to myself and say you’re going to put it in.
“After about the 80-minute mark you starting thinking this could go to penalties, I’m going to be definitely taking one.
“The last 30 minutes I couldn’t run anymore, I was too tired.”
Mooy converted his spot-kick in the second leg win over Sheffield Wednesday last week, which secured the Terriers a place in the final.
But the 26-year-old said you can “never really” prepare for the pressure-cooker of penalty shootout.
“They say the Germans don’t miss and we’ve got a lot of Germans, maybe that’s why,” he said.
“We had that experience [at Hillsborough] and Reading didn’t; maybe that helped.
“You still have to be lucky for the keeper not to guess your way.
“There’s a bit of luck and concentration.”
Mooy was delighted with The Terriers’ promotion to England’s top flight, describing it as one of the happiest days in his life.
“Apart from my baby’s birth and getting married, this is the best day,” Mooy said,
“It’s been a big few weeks but it’s all worth it.
“It’s crazy. It’s just been a rollercoaster, so many ups and downs, but it’s all worth it… everything’s worth it, this day.
“Lots of players don’t get to play at Wembley, so coming today is something very special… but to win and get a team promoted to the Premier League and be part of it is amazing. It’s unbelievable.”
Wagner’s side started strongly and the Australian’s cross was headed just wide by Michael Hefele in the fourth minute.
Five minutes later they should have gone 1-0 up when Isaiah Brown missed a glaringly open goal after he was put in by Elias Kachunga’s pass.
The Yorkshire club dominated the early stages with their high press and slick passing.
In the 16th minute Kachunga earned a free kick near the Royals’ box, but Chris Loewe’s shot drifted wide.
Reading were kept to long-range shots on goal in the first half.
In the second half the Royals had a great opportunity in the 47th minute when John Swift forced a good save from Terriers goalkeeper Ward.
Jaap Stam’s team grew in confidence as the game opened up and in the 53rd minute Yann Kermorgant hooked his shot high over Huddersfield’s goal, before Lewis Grabban lifted his effort wide.
In the 75th minute substitute Collin Quaner almost broke the deadlock but he scuffed Mooy’s pass.
The two teams went into extra-time with the score locked at 0-0.
Garath McCleary and Wells both drags shot wide before the dramatic penalty shootout.
Hefele missed his first but Ward thwarted Liam Kelly and Liam Moore, in between Mooy’s successful penalty, to put the Terriers a kick away from promotion, with Schindler duly obliging.
Now after 10 months in England and a memorable afternoon at Wembley, on-loan Socceroos star Mooy is Premier League-bound.
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