Manchester United manager Louis van Gaal uncertain over Wayne Rooney’s knee injury

In Manchester United’s 3-0 loss to Everton today, captain Wayne Rooney left the field with a knee injury in the waning stages of the match.

Robin van Persie replaced the Englishman in the 88th minute, fourteen minutes after Kevin Mirallas scored the final goal for the Toffees. It was a game that showed Roberto Martinez’s squad at their most clinical, getting nine shots off and seven of those on goal.

But for United, with the possibility of Rooney being out in the midst of a crucial end-of-year stretch, the hunt for a top-three finish becomes more difficult.

[RELATED: Everton-Man United full recap]

“Yes, Rooney was injured,” manager Louis van Gaal said to MUTV. “He had a shot on his knee, so we have to wait and see how heavy [serious] it is.”

If the star striker is unavailable to Van Gaal next week in a clash vs. West Brom, Radamel Falcao and Robin van Persie will hold greater responsibility, but looking at the United’s final four games, the biggest test will come against Arsenal on May 17. Competitions against the Baggies, Hull City and Crystal Palace will be perfect opportunities to pile up points, regardless of Rooney’s attendance.