Black Cats striker was subbed in the opening minutes of the 1-0 defeat to the Premier League champions and will find out extent of knee problem in the coming days
The 18-year-old, who has scored one goal this season and netted 27 times in three seasons for former club Ipswich Town, was substituted within the first five minutes of the defeat as a result of the injury.
A statement on the club's official website read: "The youngster, who has made nine appearances for the Black Cats this season, is set to have his knee looked at to assess the full extent of his injury and results will be known in the coming days."
The blow to the £8 million man, signed from Ipswich in the summer, leaves Steve Bruce with just two available forwards, loanee Nicklas Bendtner and the man who replaced Wickham at the weekend, Ji Dong-Won. However, reports have suggested that Asamoah Gyan could be recalled from United Arab Emirates side Al-Ain, where he is currently on loan.
The defeat at Old Trafford leaves Sunderland one point clear of the drop-zone, with the side having picked up only two wins in 11 league games this season.
Bruce's men will be hoping they can turn around their form with three home games against fellow strugglers and early relegation candidates Fulham, Wigan and Blackburn, after having already played the likes of Arsenal, Chelsea and Sir Alex Ferguson's men.
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