There was a time when winning the FA Cup was as prestigious a triumph as winning the league. That time has passed. The FA Cup now is a curious beast. We are told that it represents the last bastion of English football tradition. We are reminded of muddy pitches and Ronnie Radford, and yet the trophy bears the name of a corporate sponsor; the scheduling has been sliced up for television; the final kicks off at tea-time and the ball looks like a piece of hard candy. No, the FA Cup is not what it was. But Manchester United and Liverpool should play this weekend as if it is.