Steve Bruce is waiting for a news of a scan after Matt Ritchie picked up a hamstring injury at Hibs last night.
The Toon star limped off in the early stages of the 3-1 win at Easter Road and is a doubt for the Premier League opener against Arsenal.
Bruce has already identified Ritchie as one of his key players ahead of the new season.
When asked about Ritchie’s withdrawal, Bruce said: "We hope it's not serious.
“That's the awful thing at Hibs because we're a bit shy in that area.
“He'll have a scan in the next 48 hours and hopefully it's not too bad.
“He's nicked a hamstring.
"Whether it's a strain or how serious it is we do not know.”
