Agent: Valenzuela in hospital

Jockey Patrick Valenzuela, who has not ridden since the final day of the Hollywood Park spring-summer meeting on July 16, has been hospitalized since late July, according to his agent, Tom Knust. Knust would not disclose the reason for the hospitalization.

Valenzuela has been in a Los Angeles-area hospital since approximately July 21, two days after the start of the Del Mar meeting, Knust said.

Valenzuela was scheduled to appear before the stewards at Del Mar on Monday to discuss his recent absence, but did not appear.

Valenzuela stopped riding after the Hollywood meet because of back problems, Knust said, adding that Valenzuela was contemplating surgery.

In late July, Valenzuela passed drug tests administered by California Horse Racing Board investigators.

"He's sober and drug-free," Knust said.

As part of a conditional license agreement, Valenzuela can be tested for drugs by the racing board at any time, even if he is at home and is not riding.

Valenzuela, 43, has a history of substance-abuse problems. He missed the second half of 2004 because of a suspension related to an absence in early 2004. He returned to riding in early 2005.