Mac Swiney was a tenacious winner of the Vertem Futurity Trophy at Doncaster.

Jim Bolger ’s challenger, a Group Two winner on soft ground at the Curragh in August, had since managed only eighth of 10 on a quicker surface over the same course and distance in the National Stakes.

But he again revelled in testing conditions as the rain set in on Town Moor, with the 12-1 shot challenging last under Kevin Manning to overhaul eventual third Baradar and hold off 6-4 favourite One Ruler in the final furlong, scoring by three-quarters of a length.

Following a race in which Dewhurst runner-up Wembley was a significant late withdrawal on account of the ground, Paddy Power and Betfair responded by halving Mac Swiney’s odds for next year’s Derby to 20-1 from 40-1.

Manning, who was riding his first Group One winner in Britain since Pleascach won the Yorkshire Oaks in 2015, said: “He’s done all his running over seven furlongs, but I always thought the further he went the better he’d be.

“He was a little slowly away, but that enabled me to get a position. There was a bit of scrimmaging but he was able to hold his corner. He was very switched off and very relaxed.

“He’s got a great attitude and didn’t fight me through the race, but at the business end he’s there when you want him.

“I imagine he’ll start off in one of the Guineas, but I think he’s a type that the better the race the better he’ll go, as he can cruise at good gear and he’s probably got more pace than I give him credit for.

“I think he’s a horse that when he steps up in trip you can only see the best of him as a three-year-old.”

Bolger turns 79 on Christmas Day, but once again has proved he can still come up with the goods on the big days.

Manning said: “It’s great to be back winning Group Ones, we’ve had some wonderful years together and we’ve been placed in this race before, so this is another box ticked.”

The colt is named after the Irish playwright and politician Terence Macswiney, who died 100 years ago on October 25, 1920 in Brixton prison on hunger strike having been placed there charged with sedition.

Manning said: “Jim is very good at naming his horses and this one is very well named, it’s 100 years tomorrow that he died.

“Jim didn’t come because of all the rigmarole that goes with it. I know I can’t mix with the other jockeys for 14 days when I get back, but that’s the way it is, it has to be done.

“I thought this lad was worth doing it for. He’d beaten the horse that was the favourite (Wembley) in his maiden and the horse who won the Group One in France (Van Gogh) was behind him at the Curragh, so the form stacked up.”

Bolger told Sky Sports Racing: “I was hoping he could win, he’s been improving steadily.

“He’d have preferred better ground, but he got through that today and he did it really well.

“I’ve been regarding him as my Derby horse since he first went to the races and after today that is not about to change.

“I must have known he was good back in January when I named him Mac Swiney, it wouldn’t have been good for me or anyone around here to name a horse after a Cork man if he wasn’t very good.

“He’s one of our outstanding patriots and I’m thrilled for his memory that this fellow was able to go back to England 100 years after his death and win like he did.”

All in all it was a profitable day for Bolger: “It’s nice to have bred him, I also bred the Group One winner in France trained by Mark Johnston (Gear Up). I couldn’t do things like this without brilliant staff, both on the farm and in the training centre.”

Bolger also landed the Group 3 Eyrefield Stakes at Leopardstown with Flying Visit who was ridden by Luke McAteer.