Jockey Tom Bellamy was stood down from racing at Cheltenham on New Year's Day after breath samples he supplied were found to contain alcohol above the threshold level.
Bellamy was due to ride Ballymalin, Splash of Ginge and Qualando on Monday but was made to sit out by the British Horseracing Authority.
The rider was replaced by James Bowen and Tom Humphries in his first two races, with Harry Skelton riding Qualando in his stead.
The stewards' report from Cheltenham read: "The sampling officer reported that Tom Bellamy provided a sample which was found to contain alcohol above the threshold level for breath samples.
"The rider, the clerk of the scales and the sampling officer were interviewed.
"The matter was referred to the head office of the British Horseracing Authority and Bellamy was suspended from riding for the day."