Paulie Malignaggi has confirmed his retirement in the wake of Saturday's defeat to Sam Eggington.
The two-weight world champion suffered an eighth professional defeat as Egginton stopped him inside eight rounds at the O2.
Malignaggi later joined the commentary team for the David Haye v Tony Bellew fight and admitted he was "probably done" after a career which brought world titles at super-lightweight and welterweight, and an official announcement arrived late on Monday night.
He said: "Nineteen years ago today, I entered the ring for the first time as an amateur. That makes this as good a time as any to announce my retirement form competition.
"My life is in a place 19 years later that I never dreamed it could be in, and I have boxing to thank for that.
"I'm looking forward to a long, fruitful career now behind the mic, staying around the sport I love so much and the sport that changed my life for the better."
The American retires with 36 wins from his 44 pro contests, while four of his eight defeats came in world title fights.
