Sentence:  Although they believe they can overhaul their 2-0 deficit, they cannot afford to be as lethargic as this at Camp Nou, and the time is surely approaching when Manuel Pellegrini's faith in Martín Demichelis <WSD>wavers</WSD>. 
Meaning of the word marked with <WSD> tags:  To falter; become unsteady; begin to fail or give way.