DUBAI, United Arab Emirates (AP) — Defending champion Monterosso has pulled out of the $10 million Dubai World Cup.

The Emirates Racing Authority said Saturday that Monterosso, which is owned by Dubai ruler Sheik Mohammed bin Rashid al Maktoum, "is lame with left fore" and will not get the chance to become the first horse to win a second straight title.

Sheik Mohammed's Godolphin's stable has four other horses in the world's richest horse race. Mickael Barzalona, who was to ride Monterosso, will replace Kieren Fallon as the jockey on African Story, another Godolphin contender.

For the first time since the race moved to Meydan Racecourse in 2010, several American horses are contenders, led by Kentucky Derby winner Animal Kingdom and two-time Eclipse Award-winner Royal Delta.