He was injured late in Game 2 when he was on the receiving end of a brutal hit to the head by Blackhawks defenseman Brent Seabrook. Backes was clearly shaken up and struggled getting off the ice, while Seabrook was suspended for three games. The final game of that suspension is Game 5 on Friday.
This was the play.
In 74 regular season games for the Blues, Backes scored 27 goals to go with 30 assists.
The series is tied, 2-2, with Chicago coming in having won consecutive games after St. Louis won the first two games of the series at home.