OXON HILL, Md. - Doctors say boxer Maxim Dadashev had surgery at a Maryland hospital for swelling on his brain after collapsing outside the ring after losing a match.

Doctors told reporters early Saturday morning that the Russian-born boxer had surgery in a procedure that took about two hours.

The Washington Post reports that his manager, Egis, Klimas, and his strength and conditioning coach, Donatas Janusevicius, were both at the hospital, where he is expected to remain for days.

Dadashev collapsed after a loss to undefeated Subriel Matias in their 140-pound (63.5 kilogram) bout at the Theater at MGM National Harbor in Oxon Hill. Trainor James McGirt stopped the fight before the 12th-round bell.