The Romanian international was injured early in the second half of the 2-0 defeat at PSV Eindhoven, when he fell awkwardly and twisted his knee after catching a high ball. The 26-year-old stretched a knee ligament, and an MRI scan subsequently revealed he would be missing for between six and eight weeks.
Lobont will sit out the UEFA Champions League trip to Maccabi Tel-Aviv FC on 3 November as well as the visit to Juventus FC a fortnight later. His participation on Matchday 6, when Ajax welcome FC Bayern München to Amsterdam, is also in doubt.
In his absence, Maarten Stekelenburg would normally be Ajax's deputy goalkeeper but he is sidelined with a knee injury, so it was Hans Vonk who came off the bench to replace Lobont yesterday.
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