Chris Hayes received all the plaudits from Dermot Weld after partnering 10-1 shot Search For A Song to a two-and-a-quarter length win in the Comer Group International Irish St Leger.
An eighth winner of the Classic for Weld, the Moyglare Stud-owned filly was the first of her sex to win the race since Hayes won on the Weld-trained Voleuse De Coeurs in 2013.
The only three-year-old in the line-up, she became the first filly of her age to win the event for 30 years.
For the first two furlongs of the race Search For A Song was racing so keenly that hopes of victory appeared unlikely. However, Hayes decided to send the daughter of Galileo to the front under seven furlongs out and from there she was not for catching.
Kew Gardens stayed on well from behind for second with Southern France, who was supplemented for the race, third. Big-race favourite Cross Counter, last year's Melbourne Cup winner, was fourth.
Weld said: "It's a very special day and a very emotional one. It was wonderful that Pat Smullen, who rode so many big winners for Moyglare, was here for his Cancer Trials Champions Race which was so well supported by racing people and the wider public.
"Search For A Song was running so freely early on that it was either going to work out brilliantly or be a disaster. Chris made the right call and it was a very brave one and a hard one to make. He was tactically brilliant on Tarnawa in the Blandford Stakes and again excelled on this filly.
"When she got to the front the filly settled and we knew she would stay – there's a lot of stamina in her pedigree.
"The world could be her oyster next year but I'd imagine this will probably be it for this season. She was very fit and well and we knew she had come on since her Galtres win last month. It was a very good performance against such highly rated older horses."
Hayes said: "Search For A Song is a high-class filly. She's big and strong and was very keen early on. I was afraid she was doing too much but when we went to the front, she kicked on and found plenty in the straight.
"Pat [Smullen] is a good friend and has been a great mentor. I spoke to him before the race and he gave me the confidence to trust in the filly when she got into a rhythm. I knew very early on that I'd be getting into a row with her but it all worked out well."
Weld had also previously landed the race with Vintage Crop in 1993 and 1994, and four-time winner Vinnie Roe (2001-2004), as well as Voleuse De Coeurs six years ago.