The jockey of Melbourne Cup runner-up Prince Of Arran has apologised for breaking Australian racing's whip rules after being abused on social media, admitting the vitriol had "taken its toll".

Michael Walker has expressed regret for using the riding crop seven times more than allowed on the British stayer, which was eventually promoted to second in Tuesday's race.

Prince Of Arran was third across the line behind Australia's Vow And Declare, but wound up in second after stewards relegated Frankie Dettori's horse Master Of Reality from the runner-up spot for causing interference to Il Paradiso.

Walker was fined $10,000 - one of the largest fines in the race's history - and suspended for seven meetings after telling stewards his actions were spurred out of a desire to win the Melbourne Cup and that the race “wasn’t a maiden at Echuca”.