PHOENIX - For most high school seniors, Saturday means thinking about what you're going to do with your buddies and maybe even the prospect of a date.\nThose more traditional concerns were not on the mind of 18-year-old D.J. Fuller last Saturday. Fuller, who recently passed his trainer's license exam in Arizona, was putting on the tack for his first starter, Canyoutopthis, in the second race at Rillito Park near Tucson.\nCanyoutopthis, a 7-year-old mare, is owned by Chad Ferguson, D.J.'s stepdad, and Ron Ferguson, who is Chad's father. Prior to Saturday, she had been trained by Chad.\nThe stable, which is based at Turf Paradise, is a family affair. Chad and D.J.'s mother, Terri, operate Ferguson Racing along with other family members, so it wasn't long before D.J. found himself on the traditional path of mucking stalls, doing the feeding, and hotwalking the horses as he worked his way up the ladder. Terri also is a director of the Arizona Horsemen's Benevolent and Protective Association.\n"I've been around this game since I was a little kid," said D.J. "But I began to take it a lot more seriously when I was about 13 or 14."\nRacing, school, and baseball add up to a full day for the Thunderbird High School student.\n"I get to the track and work around the stable from about 5 to 8 a.m., then go to school since I don't have a first-period class," he said. "After school, I have baseball in the afternoon, and once I'm done there, I'm back to the backstretch to get some more work."\nFuller's first starter didn't have a fairy-tale finish. Canyoutopthis was sent off at 5-1 in the four-furlong dash for $1,500 claimers and finished fifth under Jerry Remer, beaten 6 3/4 lengths. Regardless, it was a watershed day for the young Fuller, who privately sold the mare after the race.\nFuller sent his second starter out Tuesday at Turf Paradise, and this time things went even better. Power Paws, a 4-year-old gelding Fuller owns and trains, went up against $3,500 claimers in the day's eighth race going 6 1/2 furlongs. Power Paws broke slowly under Remer and got up for third at 15-1, earning $550. Not a bad little payday for an 18-year-old, especially when he doesn't have to pay his trainer.\nFuller's idol, Hall of Fame trainer Bob Baffert, also started his career at Rillito. Baffert was a jockey at the time and rode his first winner at the southern Arizona track. Like Baffert, Fuller would like to make a career of training.\n"This is something I definitely want to pursue when I'm done with school," said Fuller, who is considering getting an associate's degree following high school. "And I'd obviously prefer to do it at my home track at Turf Paradise."