Irad Ortiz Jr. to ride Improbable in Kentucky Derby

Irad Ortiz Jr. will ride Improbable in the Kentucky Derby on May 4 at Churchill Downs, according to Elliott Walden, the chief executive of co-owner WinStar Farm.

Jose Ortiz, Irad's brother, rode Improbable to a second-place finish in the Arkansas Derby on Saturday. Jose Ortiz has chosen to ride Tacitus, the Wood Memorial winner, in the Kentucky Derby.

Walden said Irad Ortiz was chosen because "he's a top rider, and we won a Belmont Stakes with him with Creator."

"It made sense," Walden said Monday. "He's an Eclipse Award-winning rider."

:: DERBY WATCH: Top 20 Kentucky Derby contenders with comments from Jay Privman and Mike Watchmaker

Improbable won all three of his starts at 2, including the Grade1 Los Alamitos Futurity. He has finished second in both his starts this year, including a division of the Rebel Stakes last month.

Irad Ortiz rode Win Win Win to a second-place finish in the Blue Grass Stakes on April 6. Julian Pimentel will replace him on Win Win Win, trainer Michael Trombetta said Monday.

This will be Pimentel's first Kentucky Derby mount. In fact, he has not ridden a race at Churchill Downs in his career.

Trombetta said he and owner Charlotte Weber talked Monday afternoon and agreed to put Pimentel back on.

"He's ridden the horse well, set a track record on him," Trombetta said, referring to the Pasco Stakes at Tampa, "and he's ridden a lot for me."

According to Daily Racing Form statistics, Pimentel has ridden 361 winners for Trombetta from 1,825 mounts.

One other Derby mount was confirmed on Monday. Julien Leparoux will ride Japanese invader Master Fencer, according to his agent, Steve Bass.

Master Fencer earned a spot in the Derby via the Japanese Road to the Derby series.

According to Churchill Downs stall superintendent Steve Hargrave, via the track's publicity department, Master Fencer is scheduled to arrive at Churchill Downs on April 29 after doing his quarantine in Chicago prior to spending a few days at Keeneland.

Other riding assignments, most notably the choice of Mike Smith between Omaha Beach and Roadster, are expected in the next day or so, and will unleash a domino effect of Derby mounts.

– additional reporting by David Grening