There were just 53 horses entered on Sunday’s eight-race card, and since Arlington expanded its racing week from three to four days in July, the struggle to fill races with a diminished equine population at a track with purses barely competitive in the region has grown more intense. Average starters per race was a respectable (these days) 7.61 in May and June but is down to 6.96 in July.

SARATOGA SPRINGS, N.Y. – Any lingering doubts trainer Todd Pletcher might have had about whether Daredevil would like the grass were erased Friday when the Grade 1 winner turned in a sparkling half-mile drill with jockey Javier Castellano aboard over the Oklahoma turf course.

ARLINGTON HEIGHTS, Ill. – With a four-win Thursday – half of the eight-race card – jockey Jose Valdivia Jr. moved to within three victories, 44-41, of leading rider Mitchell Murrill at the Arlington meet.

And that is a long, long way from where Valdivia sat when, for the first time in a long career, he moved his tack to Arlington for a meet that began May 1. From the start of 2015 until that point, riding at the Gulfstream meeting, Valdivia, 40, had won just three races from 92 mounts, a far cry from his heyday as a mainstay on the Southern California circuit.

Jockey Oriana Rossi underwent seven hours of what was termed successful spinal surgery Thursday at Indiana University Healthcare Methodist Hospital in Indianapolis in the aftermath of a Wednesday spill at Indiana Grand, which also led to less serious injuries to two other jockeys.

SARATOGA SPRINGS, N.Y. – Keen Pauline, the 15-1 upset winner of the Grade 2 Black-Eyed Susan at Pimlico on May 15, will return to the races in Sunday’s Grade 1, $300,000 Coaching Club American Oaks at Saratoga. Keen Pauline was one of eight 3-year-old fillies entered Friday for the 1 1/8-mile race, which serves as a stepping-stone to the Grade 1 Alabama on Aug. 22.

Keen Pauline will face Grade 1 winners Include Betty and Curalina and the multiple graded stakes winner I’m a Chatterbox in the Coaching Club.

SARATOGA SPRINGS, N.Y. – It was champions on parade Thursday morning at Saratoga as three Eclipse Award-winning females from 2014 put in workouts here in preparation for stakes engagements.

Shortly after 5:30 a.m., Take Charge Brandi, last year’s 2-year-old filly champion, worked five furlongs in 1:02.49 on the Oklahoma training track in preparation for the Grade 1 Test on Aug. 8. About 40 minutes later, Untapable, last year’s 3-year-old filly champion, worked five furlongs in 1:01.75. She is likely to make her next start in the Grade 1 Personal Ensign on Aug. 29.

DEL MAR, Calif. – The question of whether Pure Tactics is a turf sprinter or a miler was answered in Wednesday’s $86,350 Wickerr Stakes at Del Mar. The 6-year-old horse can be called both.

Now, owner Doug Cole and trainer Doug O’Neill face a decision on which race to try in August. The options include the $80,000 Green Flash Handicap at five furlongs Aug. 19 or the $200,000 Del Mar Mile on Aug. 23.

The Grade 2 Del Mar Mile would seem a logical spot after the Wickerr.

DEL MAR, Calif. – Kung Fu Mambo, a Group 1 winner in Peru in 2012 who won his only start in the U.S. at Santa Anita last month, has been retired because of a recurring tendon injury, trainer Peter Miller said.

The decision to retire Kung Fu Mambo was made in recent days. Kung Fu Mambo was nominated for Saturday’s $200,000 San Diego Handicap at Del Mar and was considered a potential starter as recently as last weekend.

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DEL MAR, Calif. – Triple Crown winner American Pharoah gave trainer Bob Baffert goose bumps with his work Thursday at Del Mar, a drill officially timed in 1:11 for six furlongs, with American Pharoah always into the bit, eagerly looking to do more in his penultimate work for the Haskell Invitational at Monmouth Park on Aug. 2.

“He’s getting faster. I’m getting goose bumps,” Baffert said after American Pharoah completed the work, which came just five days after a demanding work Saturday.

SARATOGA SPRINGS, N.Y. – Although he is the defending champion and is ready to run off a four-month layoff, Palace is not certain to race next Saturday in the Grade 1 Vanderbilt, said trainer Linda Rice.

Palace rallied to a one-length victory over Happy My Way in the 2014 Vanderbilt and followed that win with an even better performance four weeks later, drawing away to a 3 1/2-length triumph in the Grade 1 Forego here. He has not won in his three subsequent starts, including a sixth-place finish in the Breeders’ Cup Sprint.