Sentence:  With 16 minutes left on the clock and the tension climbing through the roof, Trinh-Duc tried his luck with a penalty from just inside halfway only to push it wide, but the <WSD>unthinkable</WSD> now seemed a real possibility. 
Meaning of the word marked with <WSD> tags:  Inconceivable or unimaginable; extremely improbable in a way that goes against common sense.