Harvey Barnes is set for a lengthy spell on the sidelines, fears Newcastle United manager Eddie Howe.

The winger was forced off in the 8-0 win over Sheffield United on Sunday after only 12 minutes. 

The 25-year-old limped off the field and was pictured leaving Bramall Lane wearing a protective moon boot.

Newcastle are awaiting the results of a scan, but it remains a distinct possibility that the former Leicester City attacker could require surgery, with the injury described as 'substantial'.

And this news means that both Steve Clarke and Gareth Southgate may have a while to wait to find out where Barnes sees his international future.

Howe said: "We’re fearing it’s months rather than weeks. It’s a substantial injury. He’s been scanned and waiting on the specialist telling us if he needs surgery or not."

"It's an injury to the part of the foot just below the toe. It's a very unusual injury.

"He was very down about it because he knew it was serious. Nobody was around him when it happened, there was no tackle. He was just pushing off his foot trying to run. We will support him fully. He's a top quality player."

It was only Barnes' second start for the club since his £39m move from Leicester in the summer.

During the most recent international break, it emerged that Barnes was firmly on the radar of Clarke and the Scotland national team. 

READ MORE: Scotland manager Steve Clarke reveals why he won't be calling Harvey Barnes

The attacker qualifies to play for the country through his grandparents, much like Elliot Anderson. 

Clarke is keen on convincing both players to commit their international futures to Scotland, but Southgate and the FA have not given up hope of having the duo involved in the England set-up either.

Earlier this month, Clarke commented: “I am not going to say I haven’t spoken to Harvey, because I have. But that was a long time ago. I haven’t heard from him since. 

“I’m not saying he has to call me, but after this camp I probably still have a couple of weeks of fishing. I will be playing a bit of golf and getting ready for the October games (against Spain and France).

“I want a Che Adams, I want a Lyndon Dykes. On board from the first minute they walked in the door, on board with everyone at it. They understand what it means to everybody within the group. 

“They got the message straight away and have been fantastic for us, that’s what we want. But it doesn’t mean that you won’t explore other avenues. 

“You need to speak to people and ask, ‘Can we improve the squad? Can the squad get better?’ If that player makes it better and is fully committed to what we are trying to do as a nation then fine, bring them on board.”