Looking at this website: http://www.shawnyacoubian.com/stats.html
The boxer has pro, amateur and smoker fights listed. What’s smoker? 
I believe it’s an exhibition bout. They’re popular in the military.
Looks to be an unsanctioned bout, which pays very little if anything at all. Amateur bouts are still sanctioned by a governing body, and must presumably meet certain conditions to be licensed. Smokers appear to conform basically to the rules of boxing, but fall short of requiring these licensing conditions to be met.
At least that’s what I gathered from a web search.
So next question, of course, is why is it called a smoker?
Cuz back in da day the audience would be smoking cigarettes and cigars while watching the two guys beat the shit out of each other.