Canadian wildfire smoke and poor air quality forced the rescheduling of two professional sports matches in the north-eastern and midwestern United States. The disruption highlights how hazardous air conditions can affect outdoor sport, creating potential health risks for players, staff and spectators.

The affected fixtures were an MLB game and an MLS match, altered on Thursday amid smoke drifting south from Canada. Nearly 900 wildfires were reportedly active in Canada, with the smoke producing dangerous air quality and orange skies across parts of the Midwest and North-east.