Oscar Diaz, who collapsed after a 10th round TKO loss on Wednesday night, is currently in critical condition in a San Antonio area hospital. Diaz's welterweight fight was televised on ESPN2 Wednesday night. Anyone who has ever strapped on a pair of boxing gloves knows how insanely brave you have to be to fight for a living.

How severe was his injury? One of his promoters, Ron Katz, told ESPN.com the following:

"They had to remove the left side of his cranium in order to help the swelling go down, which apparently was very bad," Katz said. "He had a subdural hematoma [bleeding on the brain], which was taken care of. During surgery, he apparently showed movement in his arms and his brain pressure was very good, according to the doctor."

Diaz is 25 years old.

Diaz undergoes surgery to relieve swelling on the brain [ESPN]