Kieran Trippier was sent to hospital for an x-ray after a being forced off during Newcastle United's narrow win over Aston Villa.
The England full-back played through the pain barrier with a calf problem picked up against Everton in midweek.
But now faces a scan for potential foot injury with Eddie Howe saying after the game: "Kieran has gone for a scan.
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"We are keeping everything crossed that there is no break."
Howe recorded Newcastle's third win in a row in the Premier League - a feat not achieved since the days of Rafa Benitez in 2018.
He said afterwards: "There are lots of things we can improve.
"We defended heroically at times but I feel we have a lot to do still.
"We know we are in the early stages but we're pleased with the progress we are making.
"The crowd has been like this with team and me from the moment I came in. I can't thank them enough."
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