Highly regarded Union Rags stamped himself as a clear favorite for this year's Kentucky Derby with a convincing victory in Sunday's $400,000 Fountain of Youth Stakes at Gulfstream Park. The three-year-old was using the 1 1/16-mile stakes as his seasonal debut.

Trained by Michael Matz, Union Rags was the 6-5 second pick in the seven-horse field behind 4-5 favorite Discreet Dancer. The favorite's stablemate Algorithms, the 8-5 program favorite, was scratched from the race due to a popped splint in his right front leg.

"The colt has been training beautifully," said trainer Todd Pletcher in a statement. "It's an unfortunate situation. We'll monitor him closely and see how he responds."

Algorithms had won Gulfstream's Holy Bull Stakes in January.

Union Rags, ridden by Julien Leparoux, broke cleanly from the gate and settled into third as the field went up the backstretch. Discreet Dancer and jockey John Velazquez set the pace with News Pending pressing the leader.

Around the final turn Union Rags, runner-up in the Breeders' Cup Juvenile, was three wide to draw even with the two leaders and took a clear lead coming into the stretch.

Velazquez drove his mount to a commanding four-length win over News Pending followed by Discreet Dancer, Neck 'n Neck, Fort Loudon, Csaba and Casual Trick.

Union Rags, owned by Chadds Ford Stable, ran the race in 1:42.68 on a fast track.

The colt was using the Fountain of Youth as a prep for the Florida Derby on March 31. The Fountain of Youth win was worth $240,000 to bring the winner's career earnings to more than $1 million. In five starts Union Rags has four wins.

The colt, who was 7-1 in the first Kentucky Derby Future Wager this month, won his first three starts last year before losing by a head as the 11-10 favorite to Hansen in the Breeders' Cup Juvenile. He then finished second to Hansen in Eclipse Award voting for 2011 champion two-year-old.

Union Rags returned $4.40, $3.20 and $2.10. News Pending paid $10.80 and $3.60, and Discreet Dancer paid $2.10 to show.