Johnny Buff Ring Record Book has him born on June 12, 1888, Boxrec has November 26, 1891 and he started his Pro career on January 28, 1919.
Campbell discovered his first gym, which also gave him his Galaxxy Warrior nickname: Boxing at the Galaxxy. The year was 1997, and Campbell was 24 years old. While still working at Winn-Dixie, Campbell won every state tournament he entered in 1997, 1998 and 1999 including the Sunshine State Games and the Golden Gloves. He also qualified for the Eastern Olympic Trials to be held in Scranton, Pa., but Campbell decided to turn pro because, "I had three kids and they couldn't eat trophies." So on Feb. 5, 2000, when he was just 4 weeks short of his 28th birthday, Campbell won his debut fight, a first-round technical knockout over Scoey Fields, who weighed 143 pounds to Campbell's 137 1/4.
Luis 'Lumumba' Estaba began his professional career in 1967 at age 29, became WBC light flyweight world champion in 1975, and defended that title 12 times in the next three years. I don't know that he could be characterized as a true ATG, but he had the latest professional start of any world champion with over ten successful title defenses that I've been able to identify so far.ld