From another article...The St Louis game would be iffy, but Chicago should be safe.Is he leaving PSG right now or not until after their Aug 5th match?
Miami plays at St Louis in the middle of July and at Chicago early October. Those are the only two games in the midwest.
Messi, whose contract with Paris Saint-Germain officially expires at the end of June, could debut for Miami in either July or August — and would have the unenviable task of lifting a last-place, frequently dysfunctional franchise to the playoffs.
Reports: Lionel Messi chooses Inter Miami, MLS over Barca and Saudi Arabia
After a years-long pursuit, Messi, the world's greatest player, is reportedly coming to MLS.
sports.yahoo.com