Summary:
Manchester United have ruled out one of their key players for the rest of the season with a groin injury.

Full article:
Manchester United centre back Chris Smalling will be assessed on Tuesday after sustaining a suspected muscle tear against Southampton. Smalling had to be replaced by team-mate Jonny Evans in the 18th minute after picking up a groin injury during Manchester United's 2-1 Premier League win against Southampton at St Mary's. The England defender's is the 43rd injury picked up by a United player since Louis van Gaal took over the reins at Old Trafford in the summer. Chris Smalling, pictured with Marcos Rojo, sustained a groin problem during his side's 2-1 win at St Mary's . Manchester United defender Smalling leaves the pitch after picking up a groin injury . Smalling, who has started Manchester United's last four games, will be hoping he is passed fit to feature in his side's next match against Liverpool at the weekend. Van Gaal was unable to call on the services of the 25-year-old's fellow defenders Luke Shaw, Rafael and Phil Jones for United's trip to Southampton. The Dutchman started the match with five at the back with Antonio Valencia, Marcos Rojo, Paddy McNair, Ashley Young and Smalling all occupying defensive positions. Louis van Gaal's side were able to claim all three points despite losing Smalling during the first half .