Jockey Sonny Ho was in critical condition Thursday after emergency surgery Wednesday night at Highland Hospital in Oakland, Calif., to stop bleeding in his brain after a spill in Wednesday's seventh race at Golden Gate Fields.

Ho, 44, was hurt when his mount, Sport Boy Tommy, suffered a fatal injury, fracturing his right front cannon bone. Ho got up on his own and did not lose consciousness but became nauseous and stopped breathing while preparing to go to the Alta Bates Medical Center in Berkeley for precautionary X-rays.

A quarantine at Philadelphia Park in Pennsylvania may be extended 10 days because of uncertainty over whether a filly euthanized Feb. 23 had contracted equine herpesvirus, track officials said Thursday.

Sal Sinatra, Philadelphia Park's director of racing, said that the track is still awaiting spinal-tissue tests results to confirm whether the filly, Kari Oakie, had the highly contagious disease. An initial nasal swab taken from the filly after she was euthanized tested positive for equine herpesvirus, the first finding of the disease at Philadelphia.

ARCADIA, Calif. - Around about 8:30 on Thursday morning at Santa Anita, on a cool, crisp, clear morning that perfectly framed the nearby San Gabriel Mountains, the future book favorite for the Kentucky Derby came on the track for his final tune-up for Saturday's Grade 2, $200,000 Santa Catalina Stakes.

ARCADIA, Calif. - With 14 entrants in Saturday's $300,000 Frank Kilroe Mile on turf at Santa Anita, racing luck will have as much to do with the result as a contender's last race or workout.

No matter how well prepared a horse is, it won't matter if he is stuck in traffic or is wide in the final three furlongs.

"The turf races are a lot like Nascar," trainer Bob Baffert said. "It's whoever gets the trip."

ARCADIA, Calif. - There was a slight chance of rain Thursday night in this area, and it could have a major impact on the Grade 3, $100,000 Baldwin Stakes on Saturday at Santa Anita.

The Baldwin, for 3-year-olds, is scheduled for 6 1/2 furlongs on the hillside turf course, which requires runners to cross the main track at the top of the stretch. If there's still significant moisture in the main track, the race would be moved from the turf course and that would make Da Stoops a heavy favorite. If the rain is minimal, and the track dry, the race will stay on the turf.

ARCADIA, Calif. - A few weeks ago, Bobby Frankel glanced through the condition book for Saturday's program at Santa Anita and speculated that he would have 13 entrants. He was wrong. The Hall of Fame trainer has 14 horses entered on an 11-race program that has total purses of $2,058,000.

PORTLAND, Ore. - Cascades Express will be a heavy choice when she meets four intrepid challengers in Saturday's $10,000 Mary Goldblatt Stakes, a one-mile race for Oregon-bred 3-year-old fillies at Portland Meadows.

Cascades Express, a daughter of Cascadian from the barn of trainer Jonathan Nance, has proven to be among the top 3-year-old fillies on the grounds. She ran second to Royal Snowflight in the six-furlong Lassie Stakes in December and was again second, to entrymate Lawanda, when last seen in the Jan. 7 Mt. St. Helens Stakes at a mile.

Great Seneca, wiring the Dancing Count on Jan. 1, is 3 for 3 in his career.

A pair of confirmed front-runners trained by the Capuano brothers will attempt to lock horns without dueling each other into defeat in Saturday's $75,000 Horatius Stakes for 3-year-old sprinters at Laurel Park.

Great Seneca, trained by Gary Capuano, is seeking his fourth victory in as many starts. To do so, he will have to prove he can outrun Rainbow Inthestorm, an equally speedy sprinter trained by Gary's older brother Dale.

Pitanga, fourth behind House of Fortune in her 2006 debut in the $500,000 Sunshine Millions Distaff, moves to a more comfortable class level on Saturday, when she tops a field of 10 fillies and mares in the $60,000 Wayward Lass Stakes at 1 1/16 miles on the main track.

HOT SPRINGS, Ark. - Unbridled Sidney's options are being broadened this year. A mare who built her reputation on turf, Unbridled Sidney will open up her season on dirt Saturday, in the $50,000 Spring Fever at Oaklawn Park.

Unbridled Sidney will meet six other fillies and mares in the 5 1/2-furlong race, among them stakes winners More Moonlight, True Tails, and Timeless Dreamer. The field also includes Platinum Princess, Lila Kay's Rose, and Miss Elsie, the runner-up to Grade 1 winner Round Pond in an optional claimer at Oaklawn on Feb. 16.