St. Louis sustained the injury during Sunday night's game against the Florida Panthers. The Rangers won the game 2–1.
According to the New York Post, it is a right knee injury.
The 39-year-old St. Louis is third on the team with 47 points—20 goals and 27 assists.
New York acquired St. Louis last season from the Tampa Bay Lightning. The forward has played in six All-Star Games and won the Hart Memorial Trophy in 2003-04.
New York (44–17–7) hosts the Chicago Blackhawks on Wednesday.
- Molly Geary