How much will the world's highest-rated racehorse earn at stud?

Flightline could earn up to $50 million in his first year at Lane End's Farm based on a stud fee it is estimated may reach in the region of $200,000.

The world's highest-rated racehorse, who has been compared to the legendary Secretariat, was retired on Sunday after maintaining his unbeaten record with a resounding success in the Breeders' Cup Classic.

Flightline cost $1m as a yearling and the son of leading sire Tapit was estimated to be worth between $50 and $60m after powering 19 and a quarter lengths clear of Country Grammer in the Pacific Classic in September. A 2.5 per cent share in Flightline sold for $4.6m on Monday, which would suggest his total value is actually around $184m.