Yes he does have Asian in him
Damon was born in Fort Riley, Kansas, though he spent most of his early years in Thailand. His mother, Yome, is from Thailand and his father, Jimmy, is American of Croatian and Irish descent. They met while his father, a staff sergeant in the United States Army, was stationed in Thailand. Johnny, their 2nd child (after James, Jr.), was born at Ft. Riley, an Army base in Kansas. Johnny spent much of his early childhood as an "Army brat," moving to several bases from Okinawa, Japan, to West Germany before his father left the Army and settled the family in the Orlando area while Johnny was still a pre-schooler.
Damon was a quiet child, largely on account of a stuttering problem. "My thoughts just raced ahead of my tongue," says Damon of his problem then. "I’d sing songs as therapy, and I got better, but I just kept quiet most of the time."  Damon attended Dr. Phillips High School in Orlando, Florida when during his senior year in 1992, he was rated the top high school prospect in the country by Baseball America, was named to USA Today's High School All-America team, and was the Florida Gatorade Player of the Year. Damon also played football in high school, once getting hit by Warren Sapp and sustaining the first concussion in his life.