The debut of Polish star Robert Lewandowski in Major League Soccer has been postponed after his new team Chicago Fire's match against Vancouver Whitecaps, scheduled for Thursday, was delayed due to poor air quality caused by wildfires. Smoke from wildfires raging in the Canadian province of Ontario spread across the United States on Thursday, causing severe air pollution in border states, particularly Minnesota, Wisconsin, Michigan, and Illinois. Chicago Fire announced in a statement that the match scheduled at their home stadium has been postponed to October 6th. The statement added: 'The decision to reschedule the match was made after close consultations with local health experts, the league, Vancouver Whitecaps, and the city of Chicago.' Around 40,000 fans were expected at Soldier Field for the match, which was part of the league's resumption after its pause during the World Cup. Lewandowski, who joined from Barcelona on a free transfer after helping the Catalan club win the Spanish league title last month, was expected to play his first minutes in MLS in a match that would have paired him with his former Bayern Munich teammate Thomas Müller. The next opportunity for Poland's all-time top scorer to make his debut will be next Wednesday against Inter Miami, who will be without Argentine star Lionel Messi as he is busy playing in the World Cup final on Sunday in New York. Illinois was among the U.S. states most affected by the wildfire smoke. A smoky haze also hung over the New York City area, and New York state authorities warned of fine particulate levels from the fires, stating that being outdoors would be unhealthy.