Im not sure if this is the right place but..

[brunoafh]

This is a retro game forum, not a pro athlete signature analysis forum. The fact that the signature is on a video game is irrelevant, really.

Take it to Pawn Stars man.

[interestedperson]

I'm sorry. I wasn't sure that racketboy was just for retro. I doubt I'll go through the trouble of going to pawn stars.

[BurningDoom]

If you take it to a convention, there are often autograph authenticators there (for a fee, of course). You'll get a certificate of authentication if it's legit.

[interestedperson]

I'll look into it. Maybe there are some near me.

[Lazer]

It matches the signature on the basketball!