Newcastle are sweating over the fitness of midfielder Hatem Ben Arfa after he was stretchered off and taken to hospital during the club's goalless draw with Sporting Kansas City.
Ben Arfa missed most of last season after suffering a broken leg in a challenge with Manchester City midfielder Nigel de Jong, but Newcastle decided to complete a permanent move for the player who was originally on loan from Marseille.
The France international will now take no further part in the tour of the United States and will be flown back to Newcastle for further assessment to the ankle injury suffered in a challenge by Roger Espinoza, but he seems certain to miss the start of the Premier League season in just over three weeks.
A club statement said: "Hatem Ben Arfa sustained an injury to his left ankle in a tackle during the club's friendly against Sporting Kansas on Wednesday evening and went to a local hospital for a precautionary X-ray.
"Consequently he will be leaving the club's US tour tomorrow and the injury will be reassessed over the next 48 hours.''
Manager Alan Pardew, who remains in the hunt for a striker before the closure of the transfer window, was hoping Ben Arfa could play as an auxiliary frontman while his search continues, and he faces an anxious wait, although initial indications are that the latest injury is not too serious.
Summer signings Sylvain Marveaux and Demba Ba made debuts for the club at the Livestrong Stadium. Newcastle face Orlando City during the early hours of Sunday morning and Columbus Crew three days later.
Pardew told the club's official website: ``Hatem is going to have a few demons from that injury he had last year. I am hoping he's okay. We took him off as a precaution - he was a bit shocked by the challenge, I think - but we think he will be okay.''
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