On Thursday night in the middle of a National Hockey League game between the Chicago Blackhawks and the Winnipeg Jets, an unfamiliar figure in a No. 90 Blackhawks jersey stepped onto the ice at the United Center.

“Hey, who’s this guy?” an announcer joked.

That guy was Scott Foster, the team’s emergency goalie, a 36-year-old accountant who hadn’t played in a high-stakes hockey game in more than 10 years. He played hockey for Western Michigan University from 2002 to 2005 and plays in an amateur league, albeit a high-level one composed of former college and professional players. His venue most of the time is not the Blackhawks’ United Center, with a capacity of 23,000, but Johnny’s Ice House in Chicago’s elite league.