When a trainer suspects that one of his horses is endowed with special talent, the toughest part of his job may be to keep from getting too excited. Promising horses are frequently ruined because they are asked to do too much, too soon.

For months, trainer Dick Small has been resisting this temptation. The Pimlico-based horseman has been eager to find out just how good his colt Broad Brush is, but he has managed him cautiously and picked his spots carefully. The 3-year-old has earned $386,943 without ever being subjected to a difficult challenge.

But with the Kentucky Derby 2 1/2 weeks away, Small knows it is time to find out what kind of stuff Broad Brush is made of. So on Saturday he will bypass easier pickings elsewhere and run in the prestigious Wood Memorial Stakes at Aqueduct, where he will face Tasso, Mogambo and other top members of his generation. If he fares well, he will earn a trip to Churchill Downs.

Much handicapping logic suggests that Broad Brush will finally find himself over his head, but Small thinks otherwise. He has been looking forward to this moment of truth for a long time.

"I thought way, way back that this horse was going to go a long way," Small said. "He's real fast, but we never ran him in a short race on purpose. Rather than find out out how fast he'd go, I wanted to find out how far. And I wanted to be very careful with him, letting him go into races that were a little bit tougher each time he ran."

As a 2-year-old, Broad Brush lost his racing debut, then successively won a maiden race, an allowance race and a minor stake. He lost his first start as a 3-year-old, then captured the $75,000 General George Stakes at Pimlico, the $100,000 Federico Tesio Stakes at Pimlico and the $350,000 Jim Beam Stakes at Latonia.

But the victories didn't convince anybody that Broad Brush is a legitimate Derby contender. His times weren't exceptional, and he was winning by modest margins over relatively weak fields.

Small thinks those narrow victories are deceiving.

"My feeling is that everything he's done so far he's done quite easily. I think he's just been playing around. At Pimlico [when Broad Brush held off Fobby Forbes by a nose], it may have looked like he was really extended, but when he got to the front he started goofing off.

"I think he has a short attention span. At Latonia, it looked like he was stopping, and three strong horses were running at him. It looked like he was beaten, but he came back and opened up a couple lengths on them with no problem."

Small could have found another easy spot for Broad Brush this weekend. The $500,000 Arkansas Derby is drawing a very weak field. So is the $200,000 Garden State Stakes; two of the favorites for that event, Fobby Forbes and Miracle Wood, are horses Broad Brush beat in his last two starts. The Wood field, however, is loaded with talent.

As such, it is the race that will tell Small and owner Robert Meyerhoff whether their colt belongs in the Kentucky Derby. "We don't want to go to Louisville just for the sake of going. We know Broad Brush hasn't run against good horses yet, so the Wood is the acid test."

Even though the favorites are trained by some of the most successful horsemen in America, Broad Brush has been prepared for the Wood as skillfully and intelligently as any of them. Small has done his job; now it's up to the horse.