Bricks were thrown from a flyover at Bradford City football team's coach following Saturday's game at Rotherham.
The club's secretary said it could have turned into a major disaster
The Bantams were travelling back from their 1-1 draw at Millmoor when two youths hurled the missiles from a bridge near junction 40 on the M1.
The bricks hit the coach but the driver managed to keep control of the vehicle. West Yorkshire Police said they are now searching for two youths.
Club secretary Jon Pollard said it could have caused a major disaster.
"If the bricks had been a few inches lower they would have hit the windscreen right in front of the driver's face," he said.
"There was one hell of a bang when they hit the coach and the top of the windscreen is a mess.
"Thankfully he [the driver] was able to keep complete control of the vehicle and got us back safe."