Jockey Josh Boyd remains in "critical condition under evaluation" after he was thrown from his horse and trampled by another in the seventh race at Sunland Park Racetrack and Casino last Sunday.Boyd, 29, suffered a severe brain injury when his horse, Cuervo Brown, broke down in a maiden special weight race for 3-year-olds. New Car Cavier, a trailing horse ridden by J.R. Coates, struck Boyd while he was still in motion from his fall. Cuervo Brown was later euthanized.Boyd's agent, Laurie Madrid, said it was an unfortunate accident that couldn't be prevented. "The seven horse was right behind him," Madrid said. "He veered to the left and that put the six right on top of (Boyd). There was nothing anybody could do. It was one of those very unfortunate things."Boyd was taken to Thomason Hospital in El Paso, Texas, where he underwent surgery to remove part of his skull and brain in order to relieve pressure, Madrid said. His right eyeball was dislocated during the spill and was replaced in its socket. Boyd also had various injuries including minor cracks in two of his ribs. "Sunland Park employees and the ambulance (service) and everyone involved did an excellent job working on him and getting him transported," said Madrid, who indicated she also was speaking on behalf of Boyd's family.Boyd's spill came the same day jockey Gary Boulanger was injured in a race at Gulfstream Park. Boulanger underwent surgery to remove his spleen and a blood clot on his brain. His condition was serious at last report.After Boulanger's accident, Gulfstream Park announced it has increased its on-track medical insurance for jockeys from $100,000 to $500,000 through the end of its current meet, which concludes April 24.Meanwhile Madrid said a silent auction and a dinner to help raise money for Boyd's recovery are in the planning stages."His medical care and rehabilitation (expenses) are going to be astronomical so we're all trying to do what we can to raise money for him," Madrid said.A fund has been set up to help pay for Boyd's medical expenses. Donations can be made to the Homestretch Church in care of the Josh Boyd Fund at 1200 Futurity Drive, Sunland Park, NM, 88063.