By James Cormack The second FA Cup semi-final of the weekend sees second-tier Coventry take on a vulnerable behemoth in Manchester United. Mark Robins has worked wonders at Coventry and the Sky Blues came ever so close to returning to the Premier League last season. Robins’ men were beaten on penalties by Luton Town in the play-off final, and they’re on the fringes of another play-off berth this time around. Back-to-back defeats leading into Sunday’s game has hindered their charge, however, with Coventry perhaps having one eye on their first FA Cup semi-final since they last won the competitio…