The boxing set is a 1910 issue. The Jeffries image:
is based on a post-training portrait of Jeff ca. June 1910.
The boxing cards have definite levels of scarcity. The four black fighters are rare, whether short printed or not saved is impossible to say, but anyone I know who has assembled the set has had those as the roughest to find.
I don't know the baseball set (i know of it but don't follow it) so I don't know how tough the boxing issue is in comparison. My purely unscientific observation is that the issue is scarce: you can find a type card pretty readily but finding a specific fighter may be a challenge and the black guys are very, very hard to find at all.