Veteran Quarter Horse jockey Cruz Mendez sustained a spinal cord injury in a spill at Los Alamitos on Saturday, and was undergoing surgery at a nearby hospital on Sunday afternoon, according to two of his friends.
There is concern that Mendez has sustained paralysis in his legs, they said.
Mendez was aboard Imm Relentless in the fifth race on Saturday evening when the filly sustained an injury and fell nearing the finish of a 400-yard time trial. Imm Relentless was euthanized because of an apparent back injury, according to a racing official.
Mendez was taken to Long Beach (Calif.) Memorial hospital.
Mendez, 40, has ranked among the leading riders at Los Alamitos for the last 15 years, winning five Quarter Horse riding titles – from 2012 through 2015, and in 2023. He ranked in the top six in the standings annually since 2011, and was second three times, including 2024 and 2025.
Mendez has won 1,184 Quarter Horse races from 6,326 mounts. He had his best season in 2012, winning 177 races with mounts that earned more than $2.8 million, a career best.
Mendez was the regular rider of Heza Dasha Fire, who won 16 of 25 starts and earned more than $2.24 million in a five-year career from 2014 to 2018. Heza Dasha Fire was the 2015 Quarter Horse World Champion.
Mendez was also the regular rider of Ima Fearless Hero, a half-brother to Heza Dasha Fire, who won 8 of 17 starts and earned more than $1,062,435 in a three-year career from 2015 to 2017.
In December 2015, Ima Fearless Hero won the $1.97 Los Alamitos Two Million Futurity a day after Mendez rode Heza Dasha Fire to a win in the $600,000 Champion of Champions, the sport’s leading race for older horses.
Overall, Mendez has won 1,247 races, including 63 for Thoroughbreds in lower-level races at Los Alamitos from 2010 to 2012.
Mendez did not have any major stakes wins in 2025. In 2024, he won the Governor’s Cup Derby with Mask Mandate, a race he won in 2023 with Future Vision.
In 2024, Mendez was presented with the Sam Thompson Memorial Jockey Award, which honors Quarter Horse riders for their success on the track and personal character. Thompson died on Christmas Day in 2008 after sustaining injuries in a spill at Los Alamitos five days earlier.
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