Some veteran, talented riders raced in the 22nd Casanova Cup today, but when the 2 1/2-mile timber steeplechase was over it was a tall, lean newcomer from Maryland who had won.

Peter Jay, 35, a newspaperman from Havre de Grace, booted home Chadds Ford to a nose victory over Helix before a Virginia point-to-point opening day crowd of some 6,000 at Spring Hill Farm.

Behind him at the finish were Randy Rouse, a nine-time winner of the race who broke an ankle after sliding off Cousin Wes between the first and second jumps; veteran Tennessee Graham, who fell with Boca Bird at the eighth bend and badly jammed a shoulder; D.M. (Mike) Smithwick, a tired fourth on Bardal after making his first start in competition since 1960 when he and his brother Paddy ruled steeplechasing; defending Seven Corners champion Mike du-Pont, third on Hami, and last year's top Virginia rider, Randy Waterman, a driving second on Helix.

Jay had put Chadds Ford, the 10-year-old son of Sir Ribot, on top after the 10th fence and kept him ahead through the firal nine jumps. In the stretch, Waterman came on with Helix but was a nose short as the horses went under the wire.