Nowra trainer Luke Price has been dealt a major blow with stable star Belle De Coeur leaving the South Coast to join Sydney's leading horseman Chris Waller.

Connections opted to remove the impressive mare from Price's care after her last run at Randwick on September 27 to combine with Waller.

Waller has won the past four NSW Trainers' Premierships and already has a commanding lead for the current season.

"She pulled up really average from her last run and the vet who has a share in the horse, has most of his horses with Chris, so that is why he has gone up there," Price said.

"Some of the other owners still have horses with me, so everything is all sweet there."

Belle De Coeur had run on well first-up this preparation to finish sixth behind new stablemate Catkins in the Group 3 Sheraco Stakes (1200m) at Rosehill on September 13.

The mare also placed three times at group level during a solid winter campaign in Queensland.

Price had been open to taking Belle De Coeur to Melbourne for the spring carnival this preparation.

"She is the best horse that I have had in my stable," he said.

"She came to me with problems and we were able to get her to the races, win a few and stakes and group place.

"She has done a good job so far, whether she can carry that on, time will tell.

"I would love to still have her in my stable. She is a horse which has problems.

"So whether her racing days are still limited . . .

"He is a very good trainer Chris, whose record speaks for itself so if anyone is going to improve her, I believe it would be Chris."

Price will continue to work with a small team of runners including seven-year-old mare Tragedy Queen, who finished a close second behind Reply Churlish in Sunday's Mollymook Cup at Nowra.

"I think she was a little bit stiff," Price said.

"She got the run at the top of the straight without having to push one out of the way. We were hoping to be a bit closer in the run than we were - we got two lengths further back then we wanted to - but she is going well that mare."

The loss of Belle De Coeur is another blow for South Coast racing after Diane Poidevin-Laine's listed-winning sprinter Fire Thunderbolt had to be euthanised less than a fortnight ago.