Leading Adelaide trainer Phillip Stokes is being kept in hospital for observation after being kicked by a horse he was unloading from a float at Gawler for a barrier trial.

Stokes suffered two broken ribs and concussion and will remain in the Royal Adelaide Hospital overnight following Monday's incident.

"Phillip was in the process of leading one of his horses off the horse float when the horse became fractious and kicked out, making contact with him," a Thoroughbred Racing SA spokesman said.

The incident comes a few days out from the Group One Blue Diamond Stakes at Caulfield in which Stokes has third favourite Samara Dancer.

The filly will gallop in front of TRSA stewards over 1000m at Morphettville on Tuesday morning as arranged.

Samara Dancer bled from one nostril when she won the fillies division of the Blue Diamond Prelude at Caulfield on February 13 and must get through the gallop before being accepted to race again.

The filly is at $7 for the Blue Diamond behind the Mick Price pair of Extreme Choice (2.60) and Flying Artie ($3.50).

Other Group One nominations for Stokes at Caulfield on Saturday are Eclair Choice in the Oakleigh Plate and Hucklebuck in the Futurity Stakes.