Leighton Aspell is set for a short spell on the sidelines after fracturing his cheekbone in a fall at Cheltenham on Friday.
The dual Grand National-winning jockey was riding the Evan Williams-trained Skewiff in a mares' handicap chase when his mount was badly hampered and he was unseated four fences from the finish.
Aspell was due to ride at Hereford and Cheltenham on Saturday and Southwell on Sunday, but his agent Dave Roberts confirmed he would not take up those rides.
Trainer Oliver Sherwood, with whom Aspell teamed up to win the 2015 Grand National with Many Clouds, said: "I believe he's fractured his cheekbone. I don't know the full extent of it and the last I heard was he was going to have some surgery.
"I'm not sure how long he'll be out for, but I don't think he'll be riding for the next three or four days anyway.
"I saw him after the fall and he was grand, apart from being a bit battered and bruised obviously. He'd also had a fall at Warwick the day before.
"I know when AP (McCoy) had a similar injury a few years ago he came back wearing a mask, so we'll see. I'm sure he'll be back soon enough - we know what these jockeys are like."
