Decisive Action was plenty green on debut but came home best of all to spring a 20/1 shock in the six furlong auction maiden at the Curragh.

He was ridden in fourth by Ben Coen as the pair passed the two pole and veered markedly right as he made progress coming to the final furlong.

The son of Rip Van Winkle got on terms with the leader Engles Rock in the final 150 yards and again edged right and bumped his rival 50 yards from home.

He then won going away by a length but had to survive a stewards enquiry. Engles Rock came in second at 12/1, a length and three parts ahead of gambled-on Scotts Honor (11/2 from 22/1 in the morning).

Ben Coen said: "We liked him coming here but we just thought six (furlongs) would be a bit sharp. We went a good, even gallop the whole way.

"He stayed at it all the way to the line, bit green when he hit the front. He's a nice horse I think.

"He was always working like a stayer at home. I'm delighted with him now. I'd say there is more improvement when we step him up in trip. He can go on any sort of ground as well."

Trainer Andrew Slattery said: “We always thought he was a nice horse but he’s bred for a mile and a half. His dam is a half-sister to Gatewood and that is probably where he will end up eventually.

“He’s lucky the weather is so bad as I was going to geld him and let him off for a while. I’ll probably go for the Final of the Series and might still geld him and let him off for a while in the summer. He works well and the further he goes the better he’ll get.

“My brother Willie bought him in Ascot for 8,000 so he’s a bit of value. That’s only the second two-year-old I’ve run this year and both of them have won. He wouldn’t be as fast as the other lad (Offline, won at Dundalk) but he’ll be a fair horse over a mile. He’s a good tough horse and stays at it well.

“He was green when Ben asked him and I suppose the heavy ground as well but he won by a length going away.”

Coen was hit with a three-day suspension for careless riding.

Additional reporting by Alan Magee