Newcastle United winger Hatem Ben Arfa is a major doubt for Saturday's visit of Premier League champions Manchester City.
The France international played and scored in Monday's 2-1 defeat at Fulham after missing four games with a hamstring strain, but subsequent scans show the injury has not yet healed fully.
"It's an unusual situation," said Newcastle boss Alan Pardew. "Hatem isn't feeling any symptoms but the scan shows that his hamstring's not very well."
Newcastle have earned just one win in their last seven league games and go into the weekend just two points above the relegation zone.
Influential midfielder Yohan Cabaye and defensive duo Steven Taylor and Ryan Taylor are all out long term, while club captain Fabricio Coloccini has been in and out of the side this season through recently through injury and suspension.
Pardew said that he could look to the transfer market in January to help bolster his squad and get the Magpies claiming up the table again.
"We look weak with the injuries we've sustained and we may need to bring in a player or two next month," he said. "We're in the market, as I'm sure a few other clubs will be too. I think there'll be movement in this window.
"We're a good side that's under-performing. There are reasons for that but we can't accept them."