Athletic Bilbao fear losing Iker Munain to a long-term injury after the forward was stretchered off in the 1-0 defeat to Zorya in the Europa League.
The 24-year-old forward, who has started all 12 matches for the Basques this season, was stretchered off in added on time clutching his right leg which appeared to be in agony.
Two years ago, Munain missed six months of action following a torn cruciate knee ligament sustained against Sevilla, although there is no indication he has suffered a repeat of that particular injury.
Igor Kharatin’s 26th minute goal was enough to give the Ukrainians a surprise victory at San Mames and leave Jose Angel Zizanda’s side with only one point from their opening two Europa League matches.
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