Sidestep, a Group Two winner for Darley during The Championships, has been ruled out of the Brisbane winter carnival.

The three-year-old has reportedly succumbed to a leg injury.

"Trainer John O'Shea has advised stewards that Sidestep has been sent for a spell and will not be accepting for this Saturday's BTC Cup at Doomben," a Racing Queensland statement said.

Sidestep was one of the early favourites for the BTC Cup ahead of Wednesday's barrier draw for the first Group One race of the Queensland winter carnival.

Under the care of ex-Darley trainer Peter Snowden, Sidestep enjoyed an autumn renaissance in winning the Group Two Royal Sovereign Stakes at Randwick last month, his second victory of the preparation.

It marked the colt's best campaign since the 2013 Sydney autumn carnival when he finished second to Overreach in the Golden Slipper.

O'Shea still has last-start Hall Mark Stakes placegetter Knoydart among BTC entries as well as two-year-old colt Mohave in the Group Two Champagne Classic.

Mohave hasn't been seen at the races since his sixth of 16 runners to stablemate Earthquake in the Blue Diamond Stakes at Caulfield in February.

He won a Blue Diamond lead-up race in January beating Cornrow and he will go into Saturday's race with a recent Randwick barrier trial placing to his credit.