50 cent, according to Emmanuel Steward. (In reality, most guys could probably beat the **** out of him, Golden Gloves my ass).
Bryant Brannon had a bullet lodged in his neck @ the time he challenged RJJ for the SMW title. According to this article here, his shooter, William "Marshall served more than a decade in prison after the 1986 shooting of well-known local boxer Bryant Brannon inside an apartment Marshall used as a crack den. Two months after his release from prison in 2000, Marshall shot Brannon again in the right hip and right thigh, ending Brannon’s boxing career."
Monzon was shot 3 times by his then-wife during an argument sometime in between his rematches w/ Briscoe & Griffith. IMO, he was never 100% the same after that, even if he did continue to defend his title for several more years.
While eating at a restaurant in 2015, the "Diamond Boy" Manuel Charr was shot three or four times in the gut by a kid he used to train, and Charr had to have both hips replaced. He came back to win the vacant WBA 'Regular" belt against Alexander Ustinov two years later. He hasn't really fought much since then, because of all the WBA nonsense, opponents testing positive for PEDs, and everything else. For all the crap Charr gets, though, it was a pretty amazing comeback.
Entertaining heavyweight who competed from late 90s to early 2000s - Derrick Jefferson, was shot in a leg which ended his college basketball career. He made a pretty good run at boxing for a late starter. On HBO They used to tell the story of Terence Crawford getting shot in a head and then driving himself to hospital.