Cousin Shay, near side, sees off Zero Fighter © Photo Healy Racing
Cousin Shay was game off the front for Siobhan Rutledge in division one of the Join On Instagram @dundalk_stadium Handicap over a mile.
The Cotai Glory gelding disputed the lead before going on after three furlongs.
He came under pressure at the two pole and was there to be shot at when Zero Fighter got on terms approaching the final furlong.
Cousin Shay answered Rutledge's call, though, and stayed on best to tough it out by a head at 4/1 from the 40/1 runner-up. Cousin Shay's stablemate Zahee kept on for third, half a length further back, at 17/2.
John McConnell said: "Plan A went out the window, nothing wanted to go on. He's a keen horse so she grabbed the bull by the horns and sent him forward.
"He switched off to a certain degree anyway. He was good and tough up the straight and she was very good and strong on him. They are a good team.
"Nice the two horses ran well (Zahee), we thought they would run well.
"He did (keep finding), he was tough. He is a tough, hardy horse and there might be more to come from him, hopefully.
"He is still a lightly-raced horse for his age so it was good to get off the mark here.
"He is not a horse you want to run week in week out, he's quite a heavy-topped horse and I think he feels it so we'll see."