I found the following example sentence in Oxford Dictionary:
O'Brien conditioned winners of 13 European Derbies during his career
In the sense that the word "condition" is a transitive and it means:
(to) make (a person or animal) fit and healthy.
But then "O' Brien made winners of 13 European Derbies fit and healthy" sounds really strange to me in a sense that "winners" refer to some people who has won some European Derby. However, searching for the meaning of "winner", it could means a animal, in this case may be a horse if O'Brien means Aidan O'Brien.
Is my guess above correct?