I don't think I've heard anyone call him "chump". There are some decent negative nicknames going around.
"Two Sandwiches" --that huge guy the Rockets had a few years back. Thomas Hamilton someting like that. Ol Hammy. "the Dream" "the Glyed" "Magic"
I don't count it as a nickname if the player dislikes it after being asked about it. For me, Air Bull.
Mike Newlin, The Shark Lewis Lloyd, Black Magic (kinda weird skin-color reference, but after all, it was the 60's. Oh, wait, no, it was the 80's.) Robert Reid, Bobby Joe Charles Barkley, Food World At some point, the whole "First initial + First syllable of last name" is going to finally hopefully jump the shark so bad that people stop. T-Mac? Come on. No M.Yao? Franchise has to be the most asking-for-criticism name ever.