Other than the quarterback, which player could each AFC North team least afford to lose to injury? Here's a look:

Baltimore Ravens: Wide receiver Torrey Smith. The Ravens can't afford to lose Smith to an injury, especially with Anquan Boldin gone. Over the past two seasons, Smith has averaged 17.1 yards per reception and scored 15 touchdowns. The group of receivers who would replace him -- Tandon Doss, David Reed, Deonte Thompson and Tommy Streeter -- have 21 career receptions combined. Baltimore would go from a proven playmaker to a big question mark. The Ravens don't have to rely heavily on their wide receivers with tight ends Dennis Pitta and Ed Dickson along with running back Ray Rice. And Jacoby Jones can stretch the field like Smith. But the Ravens don't have a reliable and consistent presence outside without Smith. Other areas where depth is a concern are the offensive line and safety.

Cincinnati Bengals: Wide receiver A.J. Green. This may sound like a similar situation to the Ravens, but this is more magnified with the Bengals. The one player on the team the Bengals can't afford to lose is Green. The Bengals have a good supporting cast at receiver with promising second-year target Mohamed Sanu and shifty slot receiver Andrew Hawkins. But neither is a dynamic playmaker like Green. The Bengals' entire offense changes without him, and it changes how defenses would play Cincinnati. Depth was a problem at receiver after the Bengals lost Sanu to a season-ending injury last season. In the final five games of the season, quarterback Andy Dalton averaged 205.4 yards passing with four touchdowns and six interceptions.

Cleveland Browns: Cornerback Joe Haden. The only established cornerback on the Browns is Haden. It's a major drop-off after that, which is why the Browns can't afford Haden to miss any time. Covering wide receivers was a problem last season, when Cleveland allowed 22 touchdowns to opposing wide receivers, tied for second most in the NFL. The Browns did the minimum to address depth at cornerback, drafting Leon McFadden in the third round and signing Chris Owens in free agency. McFadden is going to endure growing pains as a rookie, and Owens was benched at times last year when he was the nickelback for the Atlanta Falcons. The only other option at cornerback is Buster Skrine, who committed nine penalties. Needless to say, this is where the Browns are most vulnerable.

Pittsburgh Steelers: Offensive tackles. The Steelers will see one of their bigger fears play out if right tackle Mike Adams isn't ready to start training camp after getting stabbed twice in an attempted carjacking. Each of Pittsburgh's backup plans at tackle carry a great deal of concern. The Steelers can go with Guy Whimper, a free agent from the Jacksonville Jaguars who led the NFL in sacks allowed in 2011 with 14, and gave up four sacks in six starts last season. The other option is Kelvin Beachum, who started the last five games at right tackle for the Steelers last season. But moving Beachum to right tackle would hurt the interior of the line. Beachum has been working this offseason on becoming the top backup at guard and center after Willie Colon was released and Doug Legursky wasn't re-signed. In other words, Pittsburgh can't afford for Adams or left tackle Marcus Gilbert to get hurt.