Louisville, KY (My Sportsbook) - Veteran runner Einstein returns Friday to defend his crown in the $400,000 Clark Handicap at Churchill Downs. The seven- year-old will face 13 rivals in the 1 1/8-mile race.

Winner of this year's Santa Anita Handicap, Einstein will be ridden by Rajiv Maragh and start from the far outside post. Recently bought by Stronach Stables, Einstein is trained by Helen Pitts-Blasi.

Einstein is coming off an 11th-place finish in the $5 million Breeders' Cup Classic that was won by the mare Zenyatta. In addition to his Santa Anita win the seven-year-old won the Turf Classic here in May.

In June at Churchill Downs, Einstein was third to Macho Again in the Stephen Foster Handicap, fifth in the Arlington Million behind Gio Ponti and was second to Richard's Kid in the Pacific Classic. Einstein has won 11 of 29 career starts for more than $2.9 million.

Macho Again will be making his first start since finishing fourth to Summer Bird in the Jockey Club Gold Cup at Belmont Park in early October. The four- year-old colt has drawn post two with Robby Albarado returning to ride.

"I feel good about our chances," said trainer Dallas Stewart about Macho Again. "I like where we are, he loves this track."

Along with his victory in the Foster Handicap this year, Macho Again won the New Orleans Handicap in March at the Fair Grounds. His most memorable race this year was probably the Woodward at Saratoga when he was second to Rachel Alexandra.

Prior to his near victory in the Woodward, Macho Again was second to Bullsbay in the Whitney Handicap at Saratoga. In 21 lifetime starts for West Point Thoroughbreds, the colt has won six times for better than $1.8 million.

Bullsbay, owned by Mitchell Ranch, Frank Lewkowitz and Joe Rice, will break from post nine with Jeremy Rose in the saddle. The five-year-old is coming off a ninth-place result in the Breeders' Cup Classic.

Trained by Graham Motion, Bullsbay recorded wins earlier this year in the Johnson Memorial at Laurel Park and the Alysheba at Churchill Downs. He was fourth in the Stephen Foster and 10th in the Hollywood Gold Cup prior to winning the Whitney.

In the Woodward, the son of Tiznow finished third behind Rachel Alexandra and Macho Again. For his career Bullsbay has earned $885,943 with seven wins in 20 starts.

Here is the complete field for the Clark in post position order: You and I Forever, Jose Valdivia, Jr; Macho Again, Robby Albarado; Giant Oak, Shaun Bridgmohan; Demarcation, Jesus Castanon; Blame, Jamie Theriot; Anarko, Leandro Goncalves; Anak Nakal, Joe Bravo; Etched, Alan Garcia; Bullsbay, Jeremy Rose; Kiss the Kid, Paco Lopez; Timber Reserve, Kent Desormeaux; Misremembered, Victor Espinoza; Dubious Miss, Calvin Borel and Einstein, Rajiv Maragh.

The Clark is slated as the 11th race on Friday with a post-time of 4:20 P.M. (et).