The Dolphins unit that will decide the AFC East in showdown vs. Bills

That was Ramsey a few days before Miami beat the Dallas Cowboys at home in Week 16 to clinch a playoff spot. Ramsey did not end up tailing Cowboys WR CeeDee Lamb, but Fangio may want to rethink that strategy and have his best defender go wherever Buffalo Bills WR Stefon Diggs goes this Sunday with the division on the line.

"I've done it a couple years in my career a lot every week, I guess," Fangio said, per Sports Illustrated's Omar Kelly. "But when you have two corners that you think are pretty good, then you're less likely to do it."

The defense that has blossomed into a top-five unit in the league since Ramsey returned in Week 8 has become a liability, again. Now, the Dolphins will need lots more fight in them from their secondary if they have any plans on beating the Bills.

The issue at hand is the injury to the guy who usually starts opposite Ramsey. The man who has the most interceptions in the league (28) since being a second-round draft choice by Miami in 2016: Xavien Howard. The Dolphins' longest tenured player has been ruled out when they face Josh Allen at home.

Allen pretty much owns the Dolphins, who have some huge decisions to make on what to do with their defensive backfield. They could start Eli Apple, who had an awful go of it when pressed into action against the Baltimore Ravens, or undrafted free-agent Kader Kohou, who seems to play better in the slot than on the outside.

The Bills targeted Kohou with Diggs in a Week 4 tilt when Ramsey was still injured. Buffalo won 48-20, and Diggs had six grabs for 120 yards and three touchdowns.

"I didn't have a good game. That's really it," Kohou said, per Sports Illustrated's Omar Kelly.

Miami also has Nik Needham, who suffered a torn Achilles last season and has been playing himself back into form. Needham is a bit more physical with some more length than either Apple or Kohou.

If Miami does not allow Ramsey to Velcro onto Diggs, it will be a gift to Allen and the Bills.

The Dolphins need to wear Allen down and will need to contain him without top pass-rushers Bradley Chubb and Jaelan Phillips, who have both gone down with season-ending non-contact football plays in recent weeks. Miami's secondary must limit Allen's options and force him into bad decision-making for the Dolphins to have any chance at getting a victory.

Fangio will most likely leave Kohou in the slot and use the veteran Apple to be a cover corner on the outside with help over the top. Ramsey should get his wish to contain Diggs. It will be the Dolphins defensive back unit that will decide this game. If they can step up, it will force Allen to extend plays with his legs, which could translate into turnovers late in the game.