It was a 10th league win in a row for Paul Jewell's side and moves them 12 points ahead of City having played a game more.
Cardiff must beat Northampton to open up a 3 point gap on Oldham and a 4 point gap on Bristol City.
Bristol have suffered a dip in form. Only 5 points from the last 15 available including 2 draws and a defeat at home.
Wigan appear unstoppable but the other teams are having dips in form.
