Donnacha O’Brien was officially crowned Irish champion Flat jockey for the second time on the final day of the season at Naas.

The defending champion began the afternoon with a tally of 110 winners for the campaign — giving him an unassailable lead of seven over the 2017 champion jockey Colin Keane, who had a book of six rides.

It has been a titanic battle between the pair for much of the year — before O’Brien pulled clear in the final weeks — and they fittingly fought out a thrilling finish to the Irish Stallion Farms EBF Maiden on the last day. Nobel Prize and Chiricahua were the 6-4 joint-favourites under O’Brien and Keane respectively, and it was the former who claimed top honours by just a head.

O’Brien’s title race victory means he matches the feat of his older brother Joseph, who won back-to-back championships in in 2012 and 2013.

Donnacha O’Brien said: “It’s a relief to win it and to have it over and done. It’s head-frying (going for the jockeys’ championship), and I don’t know how lads like AP (McCoy) and Pat (Smullen) kept going for so many years. It drains you doing it one or two years, so I can only imagine what they went through.

“Colin (Keane) is someone I have the utmost respect for, and to ride over 100 winners in a season not riding for dad (Aidan O’Brien) or Joseph is incredible. It’s a true test of how good he is.

“I have been getting unbelievable support from the Magnier, Smith and Tabor families — and I owe everything to them and dad. To be able to ride so many good horses is a real privilege.

“I’m going on holidays tomorrow morning, so I’m looking forward to that. Everyone seems to want me to retire, but we’ll think about that on another day.”