For gods sake, is it worth arguing about crap like this. Let me act as referee for a moment, do you both agree that for a match with no goals it is called a clean sheet, therefore for a match not to be called a clean sheet then you must concede a goal, as the opposition didn’t score the match is called a clean sheet, as both goalkeepers played in that match they both have the right to say they kept a clean sheet in that game, as both did, the minutes played don’t even come into it.