There are 20 days to go until the 2011 NFL season officially begins, and 20 is a significant number for the Pittsburgh Steelers. It’s the number of division titles Pittsburgh has won since the 1970 merger, most among NFL teams in that time.

Three days after Thursday night’s opener between the New Orleans Saints and Green Bay Packers on Sept. 8, the Steelers will begin defense of their most recent AFC North crown with a grudge match against the Baltimore Ravens. In addition to playing twice a tear, these rivals have met again in the playoffs three times in the last 10 years, including last season. The Steelers were the home team for all three of those playoff games, and they won all three — just another reason why this Week 1 contest is so critical.