Sir Bevys appeared in the betting lists for the Derby in April, when he was offered at odds of 50/1.
He was backed down to 25/1, but drifted out again after appearing to lack the "dash" of a Derby winner, although  in May Bell's Life reported that his performances in training had improved.

Sir Bevys made his 1879 debut on 28 May in the 100th Derby at Epsom, where the large crowd included the Prince and Princess of Wales and other members of the Royal Family.
The day was sunny and warm, but the ground was very soft after previous heavy rain.
He started at odds of 20/1 in a field of twenty-three, with Cadogan being made the 9/2 favourite.
Ridden by George Fordham, Sir Bevys broke badly and was left many lengths behind the other runners, who were led in the early stages by Protectionaist and Caxtonian.
Fordham made up the lost ground gradually and was just behind the leading group at the turn into the straight.
In the last quarter mile Visconti went to the front and looked the likely winner, but Sir Bevys appeared "from goodness knows where" to take the lead and then hold off the challenge of the 100/1 outsider Palmbearer to win by three-quarters of a length.
Despite the defeat of the more fancied runners, the result was a popular one, mainly on account of the winning jockey: Fordham was a veteran who had returned from illness, alcoholism and near bankruptcy to win his first Derby at the age of 41.
The best contemporary explanation offered for the upset, apart from the generally low quality of the race, was that Sir Bevys was the only horse to cope successfully with the very heavy conditions.
A much later report credits Fordham with having identified a stretch of better ground on which to make his decisive move.
The winning time was the slowest for more than twenty years and remains the second slowest ever recorded.

The identity of "Mr Acton", the winning owner, was not entirely clear: it was known that he was a member of the Rothschild family, but many seemed to believe "Mr Acton" was in fact Lionel's son, Leopold de Rothschild, who was known to have won several very large bets on the race.
Subsequent events made the issue less clear: the death of Lionel de Rothschild on 3 June 1879, was reported to have made all of Sir Bevys's entries void, preventing him from running in the Grand Prix de Paris on 8 June, but the colt's entry for the St Leger was apparently unaffected.

In the St Leger at Doncaster on 10 September Sir Bevys started 3/1 joint favourite with Rayon d'Or.
Ridden by Tom Cannon, he settled towards the middle of the seventeen horse field but made no progress in the later stages and finished a remote eighth behind Rayon d'Or.
The fact that both Palmbearer and Visconti were also unplaced convinced some observers that the Derby form was virtually worthless.
By late autumn Sir Bevys had developed respiratory problems (a "roaring ailment") and was retired from racing.
Sir Bevys appeared in the betting lists for the Derby in April, when he was offered at odds of 50/1. He was backed down to 25/1, but drifted out again after appearing to lack the "dash" of a Derby winner, although  in May Bell's Life reported that his performances in training had improved.
Sir Bevys made his 1879 debut on 28 May in the 100th Derby at Epsom, where the large crowd included the Prince and Princess of Wales and other members of the Royal Family. The day was sunny and warm, but the ground was very soft after previous heavy rain. He started at odds of 20/1 in a field of twenty-three, with Cadogan being made the 9/2 favourite. Ridden by George Fordham, Sir Bevys broke badly and was left many lengths behind the other runners, who were led in the early stages by Protectionaist and Caxtonian. Fordham made up the lost ground gradually and was just behind the leading group at the turn into the straight. In the last quarter mile Visconti went to the front and looked the likely winner, but Sir Bevys appeared "from goodness knows where" to take the lead and then hold off the challenge of the 100/1 outsider Palmbearer to win by three-quarters of a length. Despite the defeat of the more fancied runners, the result was a popular one, mainly on account of the winning jockey: Fordham was a veteran who had returned from illness, alcoholism and near bankruptcy to win his first Derby at the age of 41. The best contemporary explanation offered for the upset, apart from the generally low quality of the race, was that Sir Bevys was the only horse to cope successfully with the very heavy conditions. A much later report credits Fordham with having identified a stretch of better ground on which to make his decisive move. The winning time was the slowest for more than twenty years and remains the second slowest ever recorded.
The identity of "Mr Acton", the winning owner, was not entirely clear: it was known that he was a member of the Rothschild family, but many seemed to believe "Mr Acton" was in fact Lionel's son, Leopold de Rothschild, who was known to have won several very large bets on the race. Subsequent events made the issue less clear: the death of Lionel de Rothschild on 3 June 1879, was reported to have made all of Sir Bevys's entries void, preventing him from running in the Grand Prix de Paris on 8 June, but the colt's entry for the St Leger was apparently unaffected.
In the St Leger at Doncaster on 10 September Sir Bevys started 3/1 joint favourite with Rayon d'Or. Ridden by Tom Cannon, he settled towards the middle of the seventeen horse field but made no progress in the later stages and finished a remote eighth behind Rayon d'Or. The fact that both Palmbearer and Visconti were also unplaced convinced some observers that the Derby form was virtually worthless. By late autumn Sir Bevys had developed respiratory problems (a "roaring ailment") and was retired from racing.
Sir Bevys