The son of More Than Ready, a 9/1 chance, looked to have come on from his debut fourth at Newmarket and showed a professional attitude to get the job done.
Although caught a bit wide, Zaahy travelled smoothly in the hands of Tom Queally and got a good tow into the race.
On entering the straight Queally still looked to have plenty of horse beneath him and when he went for home Zaahy quickened up in fine style to score by two and a half lengths going away.
The success gave Chapple-Hyam the first of hopefully many two-year-old winners before the season is out.
Being bred in the United States he clearly enjoyed the all-weather surface but he is a good mover who looks to have a bright future ahead of him.
Timeless Dream completed a 69/1 double on the card for Chapple-Hyam when she got up late home under Jack Mitchell in the 6f handicap.
The daughter of Oasis Dream had twice finished in the past - including her last start - so she deserved to get off the mark at the sixth attempt.