The winger sustained the injury on Saturday in a collision with Stiliyan Petrov and was stretchered off the pitch despite initially trying to run off the problem.

Boro look destined for the drop as they go into the final match of the season, away to West Ham United, second bottom and three points adrift of 17th-placed Hull City

Whether Downing will be able to feature in that match remains in doubt.

orthapaedic expert

Boro's head of medical Grant Downie told the club's official website: "We will not be able to assess the full extent of Stewart's injury until his bruising and swelling go down.

"We are still waiting for further tests and investigations to find out the best way to manage the problem.

"Stewart has already seen a leading orthopaedic expert in London and is in the best possible hands."

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