Zaccio, the Eclipse Award winner of 1980 who has jumped only twice this year following an injury, returned to championship form today and held off adriving Sailor's Clue in the stretch to win the American Grand National Steeplechase by a neck.

Only in steeplechasing could a two-horse race be rated among the classic events, and today's 2 5/8-mile 'chase over Foxfield's 18 brush jumps was a perfect example. Leading jockey John Cushman put Zaccio on top at the start and held him there until the horses went under the wire 4:58 4/5 later.

"He was getting a little lazy until that horse pulled up with us a the last," added Cushman, "and that's all he needed."

Sailor's Clue, which had won last year's Colonial Cup and had posted back-to-back victories at Rolling Rock and Fair Hill this fall, raced easily off Zaccio's flank and was content to lay back from one to four lengths over the first 17 fences.

Maloney gave the Ridgley White-trained 5-year-old the whip going into the last fence, which he bobbled slightly. Only a half length separated the two as they hit the stretch before a crowd of more than 10,000.

But Zaccio showed his class and trainer Burley Cock's favorite 5-year-old held on to win the winner's share of the $20,000 purse.