Michael O'Leary believes Davy Russell should have stayed out of the saddle rather than making a U-turn on his pre-Christmas retirement decision.
The 43-year-old, who twice rode Tiger Roll to victory in the Aintree Grand National for O'Leary, announced in January - just three weeks after saying his riding career was over - that he would be returning on a short-term basis after Gordon Elliott's number one jockey Jack Kennedy broke his leg for the fifth time.
On Thursday, Russell will ride Fury Road in the Ryanair Chase at Cheltenham for O'Leary and Elliott.
Michael O'Leary: Davy Russell has 'nothing to achieve by coming back'
"A brilliant jockey as long as he wasn't messing around with his weight," O'Leary said in an interview with ITV.
"We sacked him at the right time because he was messing with his weight. He proved us wrong, came back stronger than ever, and in recent years has been riding out of his skin.
"He’d retired and, personally, I wish he’d stayed retired. He has a young family with young children and at a certain point in time you should put your family first and not your riding career.
"When you get out at that age in your early 40s... You don’t bounce, you don’t mend the way you did before.
"Particularly if you’re married and you have children you put your family first.
"He’s had a glorious career and he has nothing to achieve by coming back and I don’t think he should’ve come out of retirement."
O'Leary also expressed concerns about Kennedy's longevity as a rider.
"I don't know whether his body will survive many more falls and the breaks he gets," said O'Leary.
"He's had very cruel fortune. He is an extraordinarily talented jockey. I hope he finds a way forward because he is a once in a generation talent."
Put to O'Leary by Matt Chapman that Kennedy's fellow Kerryman Bryan Cooper had called the owner, "a very fair man" who "doesn't hold grudges", he responded: "Honestly, I couldn't care less what people think of me, and I never have.
"Bryan's a great jockey, had a lot of success at a very young age. I'm not sure if he handled it very well. He needed to work harder, but he's learnt that lesson.
"The great thing in the last year or two is that Bryan's come back riding better than ever, working harder than ever before, and that's why he's back riding Gigginstown horses, and he's riding horses for Willie, Noel Meade and everybody else."
"He has nothing to achieve by coming back and I don't think he should have come out of retirement"
Michael O'Leary says it's time for Davy Russell to step back once again#CheltenhamFestival | #TheOpeningShow | @MCYeeehaaa pic.twitter.com/ay311VtuzE
— ITV Racing (@itvracing) March 14, 2023