He'd been working with his Group 1 winning stablemate Montefilia but Costello was overlooked in the betting as he caused an upset in the $500,000 Kypreos Group Rosehill Gold Cup (2000m) at Rosehill Gardens.
Find out what the jockeys made of their mounts:
Jay Ford (Costello): “He’s a quirky animal and he likes to do things his way but he gave me a lovely ride. The speed was nice and I was able, from a good gate, just to conserve our energy all the way. He switched off at the right time.
“Obviously it’s on a day where it’s very testing conditions and he loves the wet as it is and he is a fit horse. I thought I had the runners in front of me covered, it was just whatever was going to come off my back. He did a good job.”
Costello wins the Rosehill Gold Cup
Tim Clark (She's Ideel): “She ran enormous. Just needed a single figure draw and it wins.”
Tom Sherry (Morton's Fork): “Huge effort again. He is showing his staying ability now.”
Glyn Schofield (Mantastic): “He ran well. He stuck to his task.”
Jason Collett (Nimalee): “A bit keen early but got into a rhythm and got swamped late.”
Nash Rawiller (Think It Over): “The horse just didn’t handle the ground simple as that. Because he wasn’t comfortable he didn’t try.”
Josh Parr (Fun Fact): “No, it didn’t work.”
Robbie Dolan (Sound Of Cannons): “He ran well. He’s a real stayer but I reckon the best is ahead of him.”
Brenton Avdulla (Wu Gok): “He had a lovely run. He was beaten on the corner.”
Tommy Berry (The Candy Man): “Disappointing.”
Kathy O'Hara (Savacool): “Nice run. Probably not suited on heavy going but her run was good.”
Sam Clipperton (House Of Cartier): “I was expecting a bigger run and she was just flat today.”
Louise Day (Missybeel): “He didn’t travel at all today. A bit plain in the ground.”
Check out the replays and results for Golden Eagle Day at Rosehill Gardens