When the Bills have the ball: Everything rests on the health of LeSean McCoy, who is listed as questionable for Sunday’s game with an ankle injury he suffered in the Bills’ Week 17 victory at Miami. There’s just no parsing words here: Without him, they have little chance to win. It would take near-perfect execution offensively and big plays from Tyrod Taylor and Kelvin Benjamin against one of the best pass defenses in football.

McCoy is a weapon in the run and pass games, able to carry a heavy workload and make people miss when healthy. It’s unlikely he would be anything close to that, even if he did muster the strength to play in Buffalo’s first postseason game since January 2000.

The Bills offensive line is a good unit but has its hands full with an excellent defensive front, one that got stronger when it acquired Marcell Dareus via trade in October … from the Bills. The Jaguars can rush from multiple angles and have great cover corners outside.

Can Taylor work magic with his feet and extend plays? Maybe. He’s always played better than his statistics suggest, and yet his shortcoming has been the inability to deliver game-changing plays and drives when it matters most. This is one of the most important games of his career, and he’ll have to work the middle of the field, where the Jaguars aren’t quite as stout.

When the Jaguars have the ball: Blake Bortles was on a mini-run prior to a poor performance in the season finale, and there always will be a stigma against his ability to lead a team in crunch time against a good defense until he proves it consistently.

The Bills have some playmakers in the secondary, so Bortles can’t force passes unnecessarily. The Jaguars also have some health issues at wide receiver, where Marqise Lee and Allen Hurns have been banged up, leaving Keelan Cole and Dede Westbrook as the top remaining playmakers.

The Jaguars set the table by pounding teams with the run first and foremost, trying to get a lead and let their defense help produce turnovers and points (they have seven defensive TD's this season). Leonard Fournette has been somewhat held in check since returning from injury in November and could stand to deliver a few early blows to soften things up.

The Bills defense was a turnover-creating machine early, with an amazing plus-14 ratio in the first seven games but a net of minus-5 since. They don’t generate a huge pass rush and have been vulnerable at stopping the run at times.

Special teams: The Jaguars had kicking issues early, but that’s been settled down with Josh Lambo, who has made 19-of-20 tries. They also have some juice on punt returns with Jaydon Mickens filling that role nicely.

Overall, though, the Bills have the edge here. Their kick-return unit has been a weakness, but otherwise the Bills have been very solid across the board with a good kicking game and dependable coverage units.

Coaching: Doug Marrone gave up years on his deal to leave Buffalo and was expected to take the New York Jets job when he did but eventually ended up in Jacksonville, where he has won 11 of his 18 games since taking over late last season. Generally speaking, he has done an excellent job covering up some weaknesses and playing to the team’s strengths, and his familiarity with the Bills’ roster can’t hurt.

Sean McDermott is a rookie head coach in his first playoff game. His game-management skills have been a work in progress, with multiple head-scratching decisions early on but fewer as time has gone on.

Prediction: Without McCoy, the Bills’ chances go down significantly. This always figured to be a low-scoring affair anyway, but if he can’t go the Bills might need to pull out some tricks to pop a big play or two or be aggressive on fourth downs. The Jaguars come in with plenty of questions, too, and they also could have nerves in their first franchise playoff game in forever. But we think their defense will be the difference. Jaguars by a touchdown in a defensive battle.