If you are 'out for a duck' in cricket, you have scored no runs when you are dismissed. The expression was originally a duck's egg, the shape of the 0. (The word 'love' in tennis has a similar origin - it is the English mispronunciation of l'oeuf - the French for 'the egg').
But, in his/her defence, s/he may well not have known that Steve Finn was a cricketer (one who is not infrequently out for a duck - because batting's not his job [he's a bowler]); so that definition wouldn't have seemed relevant. Of course, in an ideal world the user of a dictionary should treat all meanings as possibly relevant, but without understanding the context it's hard to separate the wheat from the chaff.