No. 1 – Brandon Marshall

We saw firsthand on Sunday what the Denver Broncos defense looks like without Sylvester Williams and T.J. Ward – a little soft up the middle. Now imagine that defense without the team’s leading tackler and one of the best inside linebackers in the league, Brandon Marshall.

With Danny Trevathan, Marshall is part of an ILB duo that plays more like Batman and Superman than Batman and Robin. But the Broncos are incredibly thin behind them. Todd Davis, who backs up Marshall, and Corey Nelson, who backs up Trevathan, have just 77 combined snaps under their belt this year for good reason.

Marshall’s numbers aren’t eye-popping, necessarily. His 84 combined tackles are good for only 21st in the league; he has no interceptions and just 1.5 sacks. But Marshall quarterbacks a defense that is tops in yards, passing yards and sacks and ranks second in takeaways and scoring.

The Broncos have had a knack for elevating under-the-radar ILBs – think Wesley Woodyard and Joe Mays – but we saw with Marshall’s foot injury last year that Todd Davis won’t be an adequate replacement. In Week 15 last year against Cincinnati, with Marshall on the sidelines, the Bengals ran for 207 yards. It was Denver’s worst effort against the run all season by a full 74 yards.

Denver had to make do without Trevathan during the second half on Sunday when he left under concussion protocol. The Broncos maintained against a Chargers team that was playing from behind. Against the Steelers or Bengals, losing Trevathan would be big. Losing Marshall would be catastrophic.