The 25-year-old winger sustained the injury during the early stages of the Magpies’ dominant 8-0 victory over Sheffield United.
Barnes will not require surgical intervention, but there are concerns that he may not be able to feature again this year.
Speaking about the injury setback, Newcastle manager Eddie Howe provided an update on Friday.
Howe said (via The Athletic): “Harvey is going to be out for around three months. No surgery is required, which is good news, but his foot is now in a boot.
“It is an injury underneath his toe, and he has commenced his recovery process. He will need to take things slow for a period, and we will give him every opportunity to recover before gradually building him back up.”
Howe expressed the disappointment of losing Barnes at this crucial juncture in the season.
He added: “It’s come at a shocking time for Harvey and us because he was just beginning to find his rhythm.
“He had a good pre-season, was getting to know his teammates, and losing any player for a considerable period is a huge blow for us.”
“I’ve talked to him – he’s a very stable, level-headed lad and a great character.
“He’s hugely disappointed and frustrated, but he’ll have more time to spend with his family, settle down in that part of his life, and then he’ll be ready to make an impact with us.”
Barnes joined Newcastle United from Leicester City this summer and has made seven appearances in all competitions, scoring one goal and providing one assist.
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