A Group Three winner as a juvenile, he had been bitterly disappointing in three starts to date this year but was reappearing after a 90-day absence.
Making his debut in handicap company, Kenya was sent off at 20-1 under Seamie Heffernan but those who had taken a punt at big odds never had a moment of worry.
He looked the proverbial Group horse in a handicap as he cruised to a three-and-a-half-length win from Katiymann, who just got the better of Turbine for second.
It was a fourth winner on the card for O’Brien, from just five races contested.
“He was just back, but he had the class. He was a Group Three winner,” said O’Brien.
“He travelled well and saw it out well. We ran him over a mile and a quarter earlier in the year and we were going too far with him.”
He added: “Seamus was very happy with him. He could go to Leopardstown in about three weeks for a Group Three race over a mile.
“He’s also in the Boomerang on Champions Weekend.”