Young Boys can definitely not have goalkeeper David von Ballmoos in the first match against Ajax in the eighth finals of the Europa League on Thursday.
The goalkeeper did not recover from a concussion in time.
The employability of the 26-year-old Von Ballmoos was already in doubt, after he dropped out on Saturday during the league match against FC Vaduz (1-1).
He suffered a concussion in a duel with Vaduz striker Dejan Djokic.
Young Boys reports on Tuesday that Von Ballmoos will miss the game in the Johan Cruijff ArenA.
The Swiss club hopes that he can play in the return in Bern next week.
Von Ballmoos was relieved against Vaduz by the 34-year-old reserve keeper Guillaume Faivre and it seems that he will play against Ajax on Thursday.
Ajax-Young Boys starts on Thursday at 6.55 pm and is led by Italian referee Marco Guida.