The 13/8 favourite Shackleton’s Hero broke from stalls like a bullet in the DundalkStadium.com Maiden and tried to make all but, despite getting the run of the race, was unable to fend off the late thrust of Chicago Bear (11s into 15/2 before the off).

The Siyouni colt was a neck to the good at the line, with well-backed 2/1 second favourite Diderot another length and three quarters away in third on his debut.

The winner made E250,000 at Goffs as a yearling and is a from a well-established Aga Khan line being a half-brother to four winners including Group 2 winner Ebiyza.

Winning trainer Johnny Murtagh won the 1997 Irish Oaks for John Oxx on this fellow’s grandam, Ebadiyla, just a week before Cavan won their 39th Ulster Championship title when defeating Derry in Clones.

The Breffni men made it 40 Ulster titles when overcoming Donegal in Armagh yesterday.

Chicago Bear was a third winner to come out of the maiden won by Lough Derg on the polytrack on the 6th of this month, following the recent victories of Zozimus (third) and Ratib (fifth), and he had shaped respectably when finishing eighth on that initial outing.

“He's a grand horse. He was very green the first day and missed the break,” said winning rider Ben Coen.

“He came out of that very well and was doing things well at home so we thought he'd run respectable today.

“He's gone and done that well. He's still green but he will improve.

“He's a grand big horse and he'll be better next year after a winter's break, I'd say that will be the plan for him now.”

Additional reporting by Gary Carson