NEW YORK (REUTERS) - MMA fighter Justin Thornton died on Monday (Oct 4) at the age 38.
He sustained serious injuries in a Bare Knuckle Fighting Championship bout in August in Mississippi. The promotion confirmed his passing on Monday night.
"We join the rest of the combat sports community in sending our deepest condolences to his family and loved ones," BKFC president David Feldman said in a statement.
Thornton was knocked out by Dillon Cleckler in the Aug 20 heavyweight fight 19 seconds into the fight.
Cleckler, in a statement issued on Tuesday, said Thornton died of pneumonia although no official cause has been released.
Cleckler issued a statement Tuesday morning on social media.
"Justin was a fighter his entire life and deserves nothing but respect!!! My thoughts and prayers are with Justin Thornton and his family at this time. RIP warrior," Cleckler posted to Instagram.
Thornton compiled a 6-18 career record.
Amber Willard, who said she was Thornton's on-and-off girlfriend, wrote on Facebook Sept 23 that Thornton was paralysed, on a ventilator and had a lung infection but was alert.