Kentucky Derby contention was shaken up Saturday when favorite Paladin was declared out by trainer Chad Brown because of an ankle injury suffered in a workout in Florida, and Commandment and Renegade won major prep races.

Commandment ($5.80) and jockey Flavien Prat narrowly held off 7-1 The Puma in the $1 million, Grade I Florida Derby as 2-1 Chief Wallabee finished third and 7-5 favorite Nearly faded to fourth to endanger his chances of qualifying for the May 2 Kentucky Derby. It was Commandment’s second graded stakes victory for trainer Brad Cox.

Renegade ($4) and Irad Ortiz Jr. scored an authoritative win over Silent Tactic and Litmus Test in the $1.5 million, Grade I Arkansas Derby, matching the style of the Todd Pletcher-trained colt’s previous stakes win by rallying from last.

In the United Arab Emirates, the American colt Magnitude went straight to the front from the inside post and led all the way to upset Forever Young in the $12 million Dubai World Cup at Meydan Racecourse.

Four-year-old Magnitude, ridden by Jose Ortiz for trainer Steve Asmussen, paid $9 after winning his first Group 1 or Grade I race by building on the sharp form he showed in victories at Churchill Downs in Kentucky and Oaklawn Park in Arkansas.

The star Japanese 5-year-old Forever Young, trying to extend his global dominance in dirt-track racing by adding a Dubai World Cup win to his triumph in last fall’s Breeders’ Cup Classic at Del Mar and last month’s Saudi Cup in Riyadh, couldn’t go past Magnitude after tracking the front-runner in the 1-1/4-mile race and finished second with jockey Ryusei Sakai.

At Santa Anita, Rashmi ($2.80) and Kazushi Kimura controlled the Grade III Wilshire Stakes from the start as the 5-year-old mare made a successful return from a 12-month layoff for trainer Jonathan Thomas.

Kevin Modesti wrote from Los Angeles.