Neil Werrett, the part-owner of Black Caviar, has bought European Group Two winning juvenile Kool Kompany in a deal struck after the colt failed to sell in the ring.

Kool Kompany was passed in at STG730,000 ($A1.33 million) at the Doncaster Bloodstock Sale on Thursday.

The Racing Post reported he was later sold privately to Australian agent Mark Player acting on behalf of Werrett.

The colt was offered by his trainer Richard Hannon's East Everleigh Stables on behalf of Middleham Park Racing.

He will stay in training with Hannon for the time being.

Kool Kompany has been to the races eight times, recording five wins including the Group Two Curragh Railway Stakes and Maisons-Laffitte Prix Robert Papin.