The 66th running of the Fountain of Youth Stakes may turn out to be a two-horse battle at Gulfstream Park.

Undefeated Algorithms, who debuted at Belmont last June with a five-furlong sprint victory by more than five lengths, is going for his fourth straight triumph; his second at the South Florida track.

The son of Bernardini scored by a length in a 6 ½-furlong allowance contest on Dec. 16 and drew off to a five-length triumph in the Holy Bull at a mile on Jan. 29, knocking off Breeders’ Cup Juvenile champ Hansen.

Meanwhile, Union Rags will launch his sophomore season in Sunday’s feature event. The son of Dixie had his three-race win streak snapped on Nov. 5, when he came up a neck short in the BC Juvenile.

The colt has been working very well at the Palm Meadows training facility, breezing three times in February. On Sunday he went four furlongs from the gate in 48 4/5.

“He did it easy and galloped out fine,” trainer Michael Matz told Brisnet.com. “He’s ready to go. Other than running in a race, he’s as ready as he could possibly be.”

However, Union Rags will have a new rider, Julien Leparoux, because Javier Castellano opted to stick with Algorithms.

The Fountain of Youth (FOY) has been reduced to 1 1/16 miles from nine furlongs. It has been staged at six different distances since favored Twenty Thirty won the inaugural by 1 ¼ lengths at 1 1/16 miles in 1945 during Gulfstream’s third season. The purse: $5,000.

The track’s second oldest stakes contest was bumped up $150,000 from last year to $400,000 and has attracted a field of six, the smallest since ’98 when Lil’s Lad defeated three others.

Five of the past 17 winners went on to capture the Florida Derby: Quality Road, ’09; Daddy, ’07; High Fly, ’05; Vicar, ’99; and Thunder Gulch, ’95, who won the Kentucky Derby. The first FOY winner to take the Florida and Kentucky Derbies was Tim Tam in ’58.

Trainer Todd Pletcher has high hopes for Algorithms. “He came out of the Holy Bull really well. His energy is good. His weight’s good.” On Monday the horse went an easy half-mile in 49 seconds at Palm Meadows.

Pletcher is so loaded with talented 3-year-olds, that he’s also entering Discreet Dancer. The son of Discreet Cat debuted at Gulfstream on Dec. 3 with an impressive triumph by nearly 10 lengths at 5 ½ furlongs. He stretched out successfully on Jan. 7 with a front-running 5 ½-length victory.

On Monday Discreet Dancer breezed five furlongs in a bullet 1:00 1/5, best of 10 works at the distance at Palm Meadows.

Trainer Nick Zito will send out Casual Trick, a disappointing eighth in a deep Gulfstream allowance race on an off track at Gulfstream on Jan. 29. Zito decide to give the son of Bernardini a shot after he worked five furlongs in 1:00 2/5 on Jan, 19.

Casual Trick finished a game second in the Gulfstream Park Derby on New Year’s Day at 1 1/16 miles in his first try around two turns.

Fort Loudon, fourth in the Holy Bull, will try again. “We’re here at Calder,” trainer Stanley Gold said, “but don’t like to ship around. I thought Fort Loudon ran a good race off the layoff.”

Csaba (pronounced SHABA) readied for the grade 2 on Feb. 18, going four furlongs in 50 4/5 at Calder.

He was scheduled to begin his career on turf, but found all three of his initial starts moved to the main track, where he ran third, broke his maiden by 6 ¼ lengths and captured an allowance contest.

Finally, he got to try the grass in Gulfstream’s Dania Beach Stakes on Dec. 18, but wound up fifth.

“We’ve decided his wins on the main track were good enough to give him a chance in the Fountain of Youth, fully recognizing what a tough spot it is,” trainer Phil Gleaves said.