In front of a crowd of nearly 20,000, Knight opened his account at the Berkshire venue as both Illustrious Blue and King Of Dixie triumphed to give the West Sussex handler and jockey Jim Crowley an 84-1 double.
Stable stalwart Illustrious Blue (16-1) took centre stage as he had a first crack at two miles in the Moss Bros Sagaro Stakes.
Settled in rear by Crowley, the seven-year-old showed a fine turn of foot to deny the long-time leader Aajel by half a length.
“We just wanted to try him over two miles at the start of the season to see what happened and I suppose the Yorkshire Cup is the next obvious race,” said Knight.
“I didn’t put him in the Ascot Gold Cup and I think the entries have closed.”
King Of Dixie (4-1) held off the persistent challenge of red-hot favourite Cityscape in the Britain’s Got Talent Paradise Stakes.
The 4-9 jolly tried his best to assert in the closing stages but King Of Dixie hung on by a neck.
Knight said: “To have a double at Ascot with a Group Three and a Listed race, it doesn’t get much better than that.
“I don’t think I’ve had a winner here before either, third in the Ribblesdale was about the best we’ve done.”
Henry Cecil has traditionally excelled with his fillies and he looks to have another promising type in Aviate, winner of the X Factor Stakes.
Tom Queally was the last jockey to ask for an effort aboard the 6-4 favourite but when he did, she had no trouble in stretching clear to beat the fast-finishing Blue Angel by a length and three-quarters in the mile heat.
Cecil said: “I’m a little bit unsure after that. We know she will definitely get a mile and a quarter but we’re not sure about a mile and a half.
“She’s in at York and could possibly run in the Musidora as there’s not a lot else for her. She will come on a lot for it and she has had a good blow.”
Cecil once again has plenty of firepower in the three-year-old fillies division and he added: “Principal Role could run in the Pretty Polly and Timepiece will run in the Lingfield Oaks Trial.”
James Fanshawe’s Society Rock (9-2) swooped late and fast to making a winning seasonal bow in the Cleanevent Pavilion Stakes.
Pat Cosgrave was struggling to find a gap inside the final furlong but when the opportunity finally arose, the Rock Of Gibraltar colt shot through to beat Cecil’s Corporal Maddox by three-quarters of a length.
Queally was banned for two days (May 12 and 13) for careless riding on the runner-up.
Richard Hannon is already thinking in terms of Royal Ascot for Zebedee (2-7 favourite) after he defied a penalty in the Aldermore Conditions Stakes under a confident Richard Hughes.
“He’s a very nice horse and we’ve always liked him. Hughesey said he pulled up a little in front,” said Richard Hannon jnr, assistant trainer to his father.