"He's a very good horse, he's an Irish Derby victor and a Group Two-winning two-year-old as well", Moore said.
Capri gave trainer Aidan O'Brien his 18th Group 1 win of 2017 in Saturday's $939,730 St Leger Stakes at Doncaster Racecourse, the final classic race for 3-year-olds in England this year.
The trainer did not specify Capri's next race.
Ryan Moore: Now has victories in all five British Classics after previous wins in the 2,000 Guineas, 1,000 Guineas, the Derby and the Oaks. He's run in a lot of good races this year, he's a very good horse and very honest.
Crystal Ocean also mounted a challenge but Capri had enough left to see off his rivals in the mile and six-furlong contest.
JIM Crowley aims to cap a stellar season with a first Classic success when he teams up with Crystal Ocean in the William Hill St Leger. "He's done very little wrong in his career and has progressed from race to race", Moore said.
Firmly established as one of the best jockeys on the world, Moore was at his best as he drove Capri to victory over the persistent Crystal Ocean and Stradivarius.
Despite jockey Ryan Moore's global success, he had never won the Group 1 William Hill St Leger at Doncaster. "Everything had every chance, but he fought them off and was the best horse". Leger double since Nijinsky in 1970, and is expected to point toward the Prix de l'Arc de Triomphe, a race in which Enable is considered the early favorite.