Three nuggets of knowledge about Sunday's Steelers-Broncos wild-card game:
Sitting target: Ben Roethlisberger's high ankle sprain is clearly affecting his mobility, which in turn has affected his ability to handle the blitz. Roethlisberger has frustrated defenses over the years by shrugging off pass-rushers to extend plays and hit a wide receiver deep downfield. In his first 13 games, he completed 61.2 percent of his passes against the blitz (according to ESPN Stats & Information), throwing seven touchdowns and three interceptions. Since the injury, he hasn't been able to escape the pressure. As a result, his completion rate against the blitz has plummeted to 28.6 percent (6-of-21 passing). The Broncos' pass rush is led by Von Miller (11.5 sacks) and Elvis Dumervil (9.5).
Playoff road block: No one ran the ball better this year than the Denver Broncos. With running back Willis McGahee and quarterback Tim Tebow leading the ground game, the Broncos averaged 164.5 yards rushing, which is 11.5 yards more per game than anyone else in the league. The Steelers ranked eighth in run defense this season, but they are first when it comes to the playoffs. Pittsburgh hasn't allowed a 100-yard rusher in 17 consecutive postseason games, which is tied with the Redskins for the longest current streak. Teams didn't really test the Steelers' run defense this season. Opponents averaged 25 carries a game against Pittsburgh, which was the eighth fewest in the NFL.
Backup plan: The Steelers placed starting running back Rashard Mendenhall on injured reserve this week after he tore his ACL. Statistics say Pittsburgh's running game will be more explosive without him. Since the start of 2010, Mendenhall averaged 3.9 yards per carry, the fifth worst among the 28 players with at least 300 rushes in the past two seasons (according to ESPN S&I). Isaac Redman, who is expected to replace Mendenhall, is averaging 4.5 yards per carry over that span. Mendenhall also had the second fewest yards after contact (1.6 per carry) among running backs with at least 200 carries. The rest of the Steelers averaged 2.6 yards after contact.