For "personalities" sometimes you just know someone, or someone that knows someone and it works out directly and they tell their agent to just do the deal. Mostly though there are agents involved from the start and it all goes through them. I have family that know Sachin, still had to go through management though and it didn't work out. We generally only deal with people that want to be involved, if they're not emotionally attached it just never works out well in my opinion. Most sports guys are gamers and are really cool to work with.
With teams it is different, mostly you can get a competition that "owns" the rights to use player likenesses and so on. There are different collective bargaining agreements for different sports, e.g. in some sports (I cant be specific due to NDA) if you have art, say a box cover, with 4 guys on it then you pay no royalties however less than 4 and you need approval from each player and separate agreements.
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What kind of a freakin question is that!>!>!$#$#
You think I would be responsible for a game without taunts!
Can I request a taunt where Biggs pulls out his photo shop pictures after something cool has happen ross or maybe a mooning(yeah right)