Horse racing’s most famous sibling is about to get his first test.

The bay colt Nicanor, the full brother to Barbaro, is nearing his debut, an occasion that will begin to answer a question that has hovered over him since shortly after his birth: Will he, too, be a star?

His trainer, Michael Matz, who also trained Barbaro, said Nicanor should be ready for his first race by later this month or early February and will begin his career at Gulfstream Park in Hallandale Beach, Fla. Matz is not sure how good the 3-year-old Nicanor will be, but he is optimistic that he has a bright future.

“I think he’s a real nice colt, and we’ve always thought that of him,” Matz said. “He’s been working quite good. It was just that he needed some time to grow up mentally. He’s a real nice horse.”

Fifty-two days before Barbaro came onto the scene with his eye-catching victory in the 2006 Kentucky Derby, Nicanor, who also is by the sire Dynaformer out of the dam La Ville Rouge, was born. When Barbaro was euthanized on Jan. 29, 2007, because of complications from a fractured leg he sustained in the Preakness Stakes, Nicanor was thrust into the limelight amid hopes he could carry on the legacy.

Many horses race for the first time as 2-year-olds, but Nicanor was taken out of serious training last summer, when Matz determined he was growing too fast for his own good.

By mid-November, Matz got back to work with Nicanor. The colt has had six recorded workouts, the last five at Palm Meadows, a training center in Boynton Beach, Fla. Each one draws him closer to a race.

“We’re really looking forward to getting him going,” said his owner Roy Jackson, whose Lael Stables also owned Barbaro. “Nobody really knows how good a horse is going to be until they come out of the gate and you can see what they can do.”

Matz, asked if he saw any similarities between Nicanor and Barbaro, said they both had a competitive spirit.

“He has a lot of his other brother, Holy Ground, in him,” said Matz, referring to a half brother to Barbaro and Nicanor who won a small stakes race at Delaware Park. “He’s built a little more like Holy Ground than Barbaro. But he seems to be very competitive, just like Barbaro was.”

That Nicanor is a full brother to Barbaro, is no guarantee he will be a successful racehorse. Many of the sport’s best horses have had siblings that had little talent. Some 37,000 thoroughbreds are born each year in North America, and only a few go on to win major races.

Nicanor will make his debut in a maiden special weight race, which is restricted to horses that have never won. Barbaro began his career on the grass, also a possibility for Nicanor, whose most recent workout came on the grass at Palm Meadows. If Nicanor wins his first time out, he will move on to a more challenging race against tougher competition.

But no matter how he fares in his first few races, do not expect to see him in the Kentucky Derby. Horses that get off to such late starts in their careers, are rarely ready for an assignment as tough as the Derby.

Perhaps the next in line, a horse named Lentenor, will run in the 2010 Kentucky Derby. The 2-year-old, another full brother to Barbaro, is training in Ocala, Fla., where he is scheduled to go to Matz’s stable in the spring. La Ville Rouge did not deliver a foal in 2008.

For now, though, the attention is on Nicanor, his impending unveiling, and his own chances for success.

“He’s got some big shoes to fill,” Matz said. “It’s a hard thing to do, being the younger brother of Barbaro. It will always be, `There’s Barbaro’s brother’ and not `There’s Nicanor.’ But he’s a good enough horse. They’ll remember his name.”