Former UCLA coach Jim Mora's practices were so rigorous -- and his concussion protocol was so flimsy -- an ex-OL tried to kill himself ... so claims one of Mora's former top recruits in a new lawsuit.
John Lopez -- a 6-5, 305-pound offensive lineman -- says repeated concussions he suffered during Mora's practices led to his suicide attempt back in 2016.
Lopez claims after being recruited by Mora to UCLA ... he almost immediately suffered his first-ever concussion at the Bruins' August 2013 training camp in San Bernardino.
Lopez says Mora and his staff didn't take the proper steps to safely return him back to the field .