Gabby Logan presents coverage of the sixth-round tie at Stamford Bridge. The Blues are looking to reach the semi-finals for the fourth time in five seasons and enter this match as strong favourites given the struggles of the Blades in this season's Premier League. The sides have also met twice in the league this season, with Chelsea prevailing 4-1 here in November and 2-1 at Bramall Lane last month. With analysis from Micah Richards.