I saw apos guess Bulls because of the M.I.B reference on twitter..so I can't take credit. However, see the following regarding the Bulls Black Jerseys on wikipedia:
"The less-often used black uniform (often used about 10 times per season) shares the same design as the white and the red ones, except that "Bulls" is replaced with "Chicago" on the front of the jersey. Black jerseys were first introduced during Chicago's 72-win run in the 1995–96 NBA season "
What do you think?

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