Michael Vaughan: Sheffield Wednesday against Sheffield United makes me horribly nervous But the main reason Wednesday have to win is their position in the league. The frustration is that four weeks ago, they were in a great position. Suddenly, going into derby day with a five-point deficit and United having two games in hand, there is a bit of gloom around. Things have changed quickly, with defeats to Exeter, Stevenage and Chesterfield, and United winning almost every single game. The tide has definitely turned. Two months ago. the momentum was all blue. Now the tide has turned red. It's a must-win game for manager Gary Megson. The fans liked him to start with, but I always say that with a manager, it's not what they do in the first year, it's what they do after that. You get found out if you're only one-dimensional. Megson likes big players, long throws, free-kicks. He plays the percentages, like they used to in Eighties football. They lost Ben Marshall to Leicester City, one of the players who could unlock a defence with a bit of magic, and with Jermaine Johnson injured, I think they will just play the hoofing game and try to unsettle United. But my philosophy is that once you start playing teams for the second time, they know what's coming.Maybe teams have realised the way they are going to play - and are just hitting them on the counter-attack. If you look at United's form, you would fancy them. But form in a derby game means absolutely nothing. If Wednesday win tomorrow, there is half a chance they could catch United. They have some tough away games coming up, and if we win on Sunday and go on a bit of a run, potentially we could take the automatic slot. You don't want to be in the play-offs. It will be a tragedy if both teams don't go up. No disrespect to a lot of teams in League One, but there are not many glamorous games. A derby is the one match where you feel you are back in the Premier League. A full house, a massive atmosphere, and everyone's up for it. I used to go to all the games, home and away, with a mate. Now I just go when I can. At the moment my lad's six, and he is coming with me tomorrow. He is a Manchester United fan, but I'm trying to change him into a Wednesday supporter. This derby might just be the point when he turns into a proper Blue.