Cape Town - Sunderland have confirmed that defender Paddy McNair will be sidelined for the remainder of the season after rupturing his anterior cruciate ligament.
The 21-year-old Northern Ireland international suffered the injury during the first half of the Black Cats' 3-0 Premier League win over Hull City.
The former Manchester United man continued to play on for most of the game before being substituted only a few minutes from time.
Speaking to the club's official website, Sunderland manager David Moyes explained what the loss of the versatile player will mean to the struggling club.
"We won't see him again this season and all we can hope is getting him right for the start of next season," said Moyes.
"I think he'd just started to find his way in the Premier
League - even though he had experience at Manchester United - and the
games he was having were bringing him on and giving him confidence," he added.
"He probably won't have his operation for over a week because he's got a cut on his knee and they can't operate while there is an open wound, so we have to wait until that heals so it might be a week or two."
McNair received messages of support from Northern Ireland and Manchester United on their Twitter accounts.
The message from his national team read: "Paddy McNair has suffered a cruciate ligament injury and is expected to miss the rest of the season. Get well soon Paddy!"
While United posted: "Everyone at MUFC wishes you a speedy recovery, Paddy!"
Paddy McNair has suffered a cruciate ligament injury & is expected to miss the rest of the season ?? Get well soon Paddy! ???? #GAWA pic.twitter.com/PYLQSxWQqU
— Northern Ireland (@NorthernIreland) November 23, 2016
@SunderlandAFC Everyone at #MUFC wishes you a speedy recovery, Paddy!
— Manchester United (@ManUtd) November 23, 2016