The extent of an injury which has forced Snitzerland out of the Group One BTC Cup will be determined by scans on her leg and shoulder.

Trainer Gerald Ryan said the mare was working well on Friday morning when his son Blake, who was aboard, pulled her up.

"It was very sudden and when that happens it's usually a joint but that doesn't appear to be the case," Ryan said.

"It seems to be a muscle so we'll get her scanned and find out exactly what it is.

"It's such a shame because she had been working so well and there hasn't been as much rain as was predicted.

"The main thing is Snitzerland is happy and eating her feed and doesn't seem to be in pain."

The withdrawal of the Lightning Stakes winner leaves a field of seven for Saturday's BTC Cup (1200m) at Doomben with local hero Buffering the $1.85 favourite ahead of Spirit Of Boom at $5.

Snitzerland's stablemate Hot Snitzel is the third favourite at $7.50.