Western Australia is celebrating after Jokers Grin stormed home to win the $5 million Kia Quokka (1200m) at Ascot on Saturday afternoon.

In a defining moment for his career, Bernie Miller notched up just his 68th career victory, combining with long-time friend Patrick Carbery to claim the biggest prize of his training life before a packed Ascot crowd.

The Maschino gelding continued his exceptional rise, recording his seventh win from only ten starts with a devastating finishing burst.

For Miller, the win was the realisation of a lifelong dream.

“How can you put that into words?” Miller said post-race.

“Honestly, there’s so many people to thank, but how can you put the thrill of that? I’ll wake up tomorrow and still won’t be able to talk to you about it, but it’s just a dream come true.

We went back to Belmont last Saturday and Patty (Carbery) said his work was just off the charts, really. That then gave me a lot of positives about what I was doing was right. Kept on doing that and didn’t change anything.

Then here we are today. Now we’re at one of WA’s best sprinters at the moment.

I think it was about 150m (when I thought he could win). The thrill of just watching him go past me, that was just tremendous.”

Jumping from gate 13, Carbery was forced to settle Jokers Grin at the back early but produced a brilliant ride, getting onto the back of Headwall around the home turn and swinging the widest into the straight.

Despite still being several lengths off the leaders with 200m to travel, Jokers Grin produced an electrifying sprint to overhaul his rivals late, getting up by a slender 0.17 lengths.

Carbery, who has partnered Jokers Grin to 61 career wins for Miller, believes the best is yet to come for the emerging sprint star.

“Whatever happened today, you know that he’s still on the way up, he’s still maturing,” Carbery said.

“I know a lot of people say that, but that’s why Bernie’s taking so much time with him.

You guys get a buzz out of watching, but what I can feel on this horse is amazing.”

Representing the Ladbrokes slot, Jokers Grin led home a fast-finishing Headwall ($6.50) and outsider Generosity ($51) to snare the lucrative purse.

Miller confirmed that Jokers Grin will now enjoy a spell before being prepared for the Winterbottom Stakes (1200m) at the Pinnacles Carnival later this year.