The top secret negotiations did not include the alderman or nearby homeowners.
"I don't think it's a good fit for the neighborhood," said resident Don Bennecke.
The arena would expand Mccormick Place to the north side of Cermak Avenue.
It would host - among other events - 18 basketball games featuring Depaul University, which would pay $70 million of the $200 million price tag. The city and McPier - the public board that controls Mccormick Place - would provide the rest of the money.
"I'm always skeptical when we're subsidizing private development with public dollars," said 45th Ward Ald. John Arena.
"I can support the building of anything as long as it benefits the community that I serve," said 28th Ward Ald. Jason Ervin.
Ald. Pat Dowell - in whose 3rd Ward the project would be located - says she wasn't called by the mayor until hours before the proposed deal was announced. She vows to stand with the residents.
"Until I've had an opportunity to talk with them about their concerns, I'm not taking a position on the proposal that the Mayor laid out for me today," said Ald. Dowell.
Mayor Emanuel would not take questions about the deal or anything else today. He ran out the Garfield Conservatory's side door to avoid reporters.
Meanwhile, another Prairie District resident Gary Schuetz described himself as in the minority: a college basketball fan excited about the prospect.
"For me, I won't have to drive all the way to Northwestern or all the way to Allstate arena to see college basketball," said Schuetz.