Phoebe's Donkey slipped through a narrow opening along the rail to edge Aunt Hattie by a head in yesterday's $27,500-added Cameo Stakes at Laurel. Heavy Sugar, entrymate of the second-place finisher, finished a tired third, two lengths behind the top pair.

Phoebe's Donkey was ridden by Charles Cooke, who was winning his third added-money event in his 13-year career. Cooke rated Phoebe's Doneky early, then elected to make his final run along the inner rail when Aunt Hattie drifted slightly with a sixteenth of a mile to go.

The winner ran the seven furlongs in 1:25 4/5 and returned $17.40 to win. The 2-year-old daughter of Son Excellence is owned by Edgar Berman and trained by J. Willaim Boniface.

Laurel will be closed on Monday. Racing will be resumed Tuesday with the post time at 12:30 p.m.

The even-money favorite, All-American Derby winner Medley Glass, broke poorply in the 440-yard event and finished sixth. The winning time was 21.65 seconds, third fastest in the seven-year histoy of the race. CAPTION: Picture, Driving in stretch in Laurel's fourth race yesterday are, from left, Audene, William Passmore up; Gallery Miss, a $50 winner, Michael Torre, and Family First, Thomas Kupfer aboard. By James A. Parcell-The Washington Post