The United boss was forced to substitute right-back Rafael da Silva at half-time of their comfortable 4-1 victory over Aston Villa at Old Trafford.
We have injuries but we will probably know more about them tomorrow. I’ve just got to hope that Rafa’s injury isn’t too bad
The 50-year-old Red Devils boss was already without versatile midfielder Antonio Valencia and France international Patrick Evra for Saturday’s clash.
And Moyes revealed that Rafael’s injury isn’t “too bad” but Uruguayan youngster Guillermo Varela may need to be drafted in for the European clash.
“With Rafael, it’s an injury and we need to check it out,” said Moyes.
“Valencia had a bit of tendinitis in his knee, which is why he wasn’t involved. He was probably one I would have put to full-back if we had lost one, so we knew we’d be short if that was the case.
“The young boy Guillermo Varela might have got on the bench but he was injured as well so we had to juggle it around. We have injuries but we will probably know more about them tomorrow. I’ve just got to hope that Rafa’s injury isn’t too bad.”
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