New York, NY (Betting Express) - Two-time champion mare Zenyatta extended her advantage in the latest NTRA Thoroughbred Poll for March 15. The six-year-old won Saturday's Santa Margarita Handicap at Santa Anita to remain in first- place.

Zenyatta, undefeated in 15 career starts, received 16 of 20 first-place votes and 192 points. Last week she had nine top votes and 172 points. The winner of last year's Breeders' Cup Classic is one win away from tying the record of 16 consecutive lifetime wins in open competition held by Citation and Cigar. She is scheduled to start in next month's Apple Blossom Invitational at Oaklawn Park.

Reigning Horse of the Year Rachel Alexandra lost in Saturday's New Orleans Ladies at the Fair Grounds and dropped in the poll from second to third. The four-year-old filly, who was second to Zardana, did not receive any first- place votes and has 150 points. She will not start in the Apple Blossom.

Moving from third to second is Donn Handicap champ Quality Road. The four- year-old colt got the four remaining first-place votes and has 173 points.

Rounding out the top 10 are Gio Ponti, Misremembered, Presious Passion, Lookin at Lucky, Eskendereya, Zardana and Bold Chieftain.

In the three-year-old poll, 2009 champion two-year-old Lookin At Lucky moved from second to first after his win Saturday in the Rebel Stakes at Oawklawn. He received 10 first-place votes and 187 points.

Fountain of Youth winner Eskendereya is second with nine top votes and 175 points. He is set to start in this week's Florida Derby at Gulfstream Park.

The lone remaining first-place vote went to Odysseus who won Saturday's Tampa Bay Derby. His 65 points put him into eighth-place.

Following the top two colts are Conveyance, Rule, Sidney's Candy, Noble's Promise, Awesome Act, Odysseus, Dublin and Discreetly Mine.