Unbeaten in two outings at two, including a valuable sales race at the Curragh, he had not shown much so far this season.
However, back on the soft ground he appears to relish, he kicked clear under Hector Crouch to hold off the favourite Al Qawah, who was slowly away, by a length and a half.
Cox said: “I’m over the moon. I’m really pleased, as he has been a victim of the firm ground.
“I’m delighted for Olive Shaw (owner), who has been patient with the horse, and I’m delighted for Hector Crouch, who is a key member of our team at home and it is great to get a big winner like that for him.
“He has clearly shown he’s as good as he was last year and it was really nice to bag a prize like that.
“It is hard to say (if better than a handicapper). When conditions are right I think you can be brave, and he has won that well today to hopefully give him a bit of confidence going forwards.
“Olive Shaw is a great supporter and he did her proud last season and it is great to be back in that league again.”
Queen Of Bermuda stamped her class on the William Hill Firth Of Clyde Stakes.
William Haggas sent his filly over six furlongs for the first time and in testing conditions there were plenty who might have questioned her stamina.
However, she brought the strongest form into the race, having chased home impressive Flying Childers winner Soldier’s Call in France last time out.
Joe Fanning was content to bide his time as Shumookhi tried to burn them all off – as she had done at Newbury on her penultimate start – but she had no answer to the 9-2 favourite, who cruised on by to earn a 25-1 quote for next year’s Commonwealth Cup with Paddy Power.
David O’Meara’s Waarif won for the fourth time in his last six races in the William Hill Supporting The Fight Against Parkinson’s Handicap.
Having taken up the running over a furlong out under Conor McGovern, he looked a sitting duck as Fire Brigade made relentless progress from the rear.
However, the favourite’s run flattened out and Waarif won by a length.