Jeff Hendrick has been ruled out for a number of weeks after an injury suffered in training last Friday.
The Ireland international played no part in Derby County's 2-1 loss to Cardiff City on the weekend as a result, and after the game, his manager Darren Wassall revealed that he was dealing with an injury that turned out to be worse than originally feared.
Speaking to The Burton Mail, Wassall said that he would be sidelined for the next couple of weeks, stating that "we thought he had suffered a thigh strain but a scan has revealed a small tear".
"We're in the hands of the medics," he added. "He's not going to be fit this week or next week but he will be back before the end of the season"
With the club giving no definite timeline for his return, simply stating that he would be out for the "next few games", he may struggle to get back to full fitness with matches under his belt before the start of the Euros.
That would add further worries to O'Neill's plate, given goalkeeper Rob Elliot suffered a serious injury in last week's friendly game, and a number of other players such as Robbie Keane facing a race for fitness ahead of the tournament.
Via Goal
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