Jamie Mott celebrated a career highlight when he teamed with Callsign Mav to win Saturday's Sir Rupert Clarke Stakes at Caulfield.

The $1 million event was the first Group 1 success for the 34-year-old, who has battled weight issues for the entirety of his almost-20-year career in the saddle.

Mott was thrilled to realise his lifelong dream but to do it for Danny O'Brien, to whom Mott spent part of his time as an apprentice with, made it even more special.

"I always knew it was coming," Mott said. "I'm one for working hard and always believing in what you are doing. Giving up is not an option.

"I put myself in a good spot weight-wise and mind-wise this campaign and I'm thankful to Danny and the wonderful connections for keeping me on Callsign Mav."

O'Brien was thrilled to play a key role in Mott's watershed moment.

"It's a big thrill, he's just been such a gifted rider who's worked so hard over such a long period of time with his weight," O'Brien said.

"If Jamie was four or five kilos lighter he'd be a top-three metropolitan jockey. He rides as well as anyone and he's going to be a very popular victor here today.

"There's so many people that have got so much admiration for Jamie."

O'Brien would have been delighted he engaged Mott when the race evolved into a stoush between Callsign Mav, I Am Superman and Tuvalu over the concluding stages with Mott's strength getting the most out of the six-year-old son of Atlante.

At the line the $16 chance had a half-neck to spare over I Am Superman ($14), who was gallant in his final run in Australia before returning to Europe, with Tuvalu – who started $4 favourite after Ayrton and Sinawann were late scratchings due to the track downgrade – just a long-head back third.

"Today I had a softer option and I was able to travel and he really enjoyed the conditions," Mott said.

"He travelled up well into the straight and was in for the fight. He got up to Tuvalu and I felt I Am Superman coming, but he was never going to lie down."

The Sir Rupert Clarke Stakes win was Callsign Mav's fourth at the highest level, following three Group 1 wins in his native New Zealand, and the $600,000 first prize lifted his career earnings to $1.37 million.

CALLSIGN MAV

A HUGE result for @jamieleemott as he snags his first Group 1 win! pic.twitter.com/MOhBtqUZPp

— 7HorseRacing (@7horseracing) September 17, 2022