MARQUETTE, Mich. (AP) -- Lightweight David Jackson was added to the U.S. Olympic boxing team Monday after Marshall Martinez quit for unspecified personal reasons.

 Martinez, 18, who boxes for the Oscar De La Hoya Youth Center in East Los Angeles, had beaten Jackson, 24, of Seattle, in February at the Olympic box-offs. Martinez forced Jackson to take a standing 8-count in the first round and went on to win the 132-pound bout 18-4.

 "I thought Marshall looked like a gold medalist," Olympic coach Tom Mustin said. "His style was different and everybody was having trouble with him. It's a big loss for us."

  Jackson also was the alternate for the 1996 Olympics.

 "That means two Olympic team trials in a row he finished second overall in his weight class. But he didn't let that get him down," said Al Mitchell, who coached Jackson at the U.S. Olympic Education Center in Marquette. "He kept a great attitude and just kept working, and now he's an Olympian. I'm very happy for him."

  After winning the 1997 132-pound U.S. title, Jackson stopped boxing because of injuries and other personal reasons. He returned to the U.S. Olympic Education Center last year.