Harry Coffey says he is proud to be chosen to ride Melbourne Cup winner Prince Of Penzance in his return at Caulfield.

Prince Of Penzance starts his build-up to this year's Cup in Saturday's Group One Memsie Stakes (1400m).

Cup-winning jockey Michelle Payne is still weeks away from a return following a fall in May while Coffey is not long back from a stint in hospital for what he calls a tune-up before the spring carnival.

He suffers cystic fibrosis, a condition that affects the lungs and digestive system, and every four to six months he goes to hospital for five days and has another five days at home on antibiotics.

"I tried to judge it so that if I got a couple of opportunities over the spring, which it looks like I'm going to, I'd be available," Coffey said.

"My health's very good at the moment and it's easy to have good health when you're riding these good horses, but it has to be.

"When you're riding against the best you have to be at your best."

The ride on Prince Of Penzance will be Coffey's third at Group One level and he says he's thankful for trainer Darren Weir's support.

He says it's a big thrill to be on a Melbourne Cup winner but noted there's also a lot of trust.

"I suppose it's a big deal, but you know the horses, you've been riding them in trackwork and once you get on their backs you settle down and let it all unfold," Coffey said.

"He's a Melbourne Cup-winning horse and there's a lot of trust in you to get the horse around and get him back safe and sound.

"I'm very grateful for that and proud to be chosen to do it."

Prince Of Penzance, who has had one run since the Cup for second in a Group Three race at Morphettville in May, is one of four runners Weir will saddle in the Group One race.

He has $2.60 favourite Black Heart Bart, Mahuta ($6) and Palentino ($6.50) while Prince Of Penzance has been specked from $41 to $31.

"He's going really well but it's a good sharp race for him first-up," Coffey said.

"He did run really well first-up in Adelaide but the best thing is it's exciting to have him back at the track."