Film room: How the Patriots can slow down Chargers wide receiver Keenan Allen

The New England Patriots’ defensive backfield is heading into the playoffs as one of the best units in the NFL. In fact, according to advanced analytics website Pro Football Focus, the Patriots field the best secondary still remaining in the race for the Vince Lombardi Trophy. On Sunday against the Los Angeles Chargers, the unit once again needs to prove that the rating is justified when it has to go against one of the league’s better passing attacks.

One name stands out in particular when talking about the Chargers’ skill position group: Keenan Allen. The 26-year old wide receiver leads his team with 101 receptions through wild card weekend, gaining 1,133 yards in the process and also scoring six touchdowns. Allen, who was voted to his second straight Pro Bowl this season, is an outstanding player — and the Patriots know that they need to find a way to keep him in check.

“Keenan Allen’s as good a receiver there is in the National Football League — big, quick, tough after the catch, hard guy to tackle, very good route runner, an exceptional route runner, great hands, concentration,” Patriots head coach Bill Belichick said about him during a press conference earlier this week. “He can play inside, play outside, run option routes, run vertical routes, double moves, good stem route runner.”

“It doesn’t matter where you put him, he’s a problem. He’s one of the best receivers in the league,” Belichick concluded. So what do the Patriots need to do in order to slow him down? First, they should look at how the Pittsburgh Steelers tried to defend Allen to find out how he dominated them in week 13 to the tune of 14 receptions for 148 yards — both season-highs for the wideout — as well as a touchdown.

Pittsburgh made two errors that day and the very first offensive snap of the day is a perfect example of that:

NFL Game Pass

First, the Steelers opened by using its linebackers to cover Allen. While Bud Dupree is an athletic player, he lacks the short-area quickness to keep with a wide receiver for an extended period of time. Chargers quarterback Philip Rivers saw the matchup, liked it, and exploited it for 14 yards. He later also went to Allen when he was covered by T.J. Watt or L.J. Fort later during the game.

All three of the linebackers are solid players but simply not built to cover a wide receiver that is among the best route runners in the NFL. And the personnel is only one part of the problem. Pittsburgh later inserted slot cornerback and ex-Patriot Mike Hilton into its lineup to cover Allen whenever he moved to the slot, but the also had his fare share of issues — especially when he gave his assignment a free release off the line.

When being allowed to pick up steam, Allen was able to take advantage of the space by using cuts to gain further separation. Pittsburgh simply failed to challenge the receiver at the line of scrimmage and while playing press-man for 60 minutes would likely have also backfired, mixing in different styles of defensive back play might have helped limit the damage at least a little bit.

The Patriots, of course, are a team that likes to do various things in order to throw passing offenses of course. And that might be something that should help the team when it comes to slowing Allen down on Sunday. What also should help, of course, is having arguably the NFL’s best cornerback in the lineup: Stephon Gilmore, who like Allen has been voted to the Pro Bowl and who might see plenty of the wideout in three days.

Using the top cornerback one-on-one against Allen is nothing out of the ordinary. The Denver Broncos, for example, did just that in week 11. While the star wide receiver still finished with nine catches for 89 yards and a touchdown, the game was one of just five this season in which Allen averaged less than 10 yards per reception — and cornerback Chris Harris Jr. is a big reason for that.

Harris Jr. shadowed Allen for much of the game. No matter if he lined up in the slot or on the perimeter, the cornerback followed him:

NFL Game Pass

When Harris Jr. was covering him, Allen was targeted five times on the day. He caught four of the passes for 65 yards and a touchdown that appeared to be more the result of a communication error on the safety’s end as opposed to the cornerback losing his one-on-one. Overall, the Broncos fared comparatively well using this approach to defending the productive Rivers-Allen connection.

What Denver also did was be physical at the point of attack and communicate well in the secondary. The following clip of an incomplete pass in the second quarter is a good example of both, as it shows Harris Jr. get his hands on the wide receiver before playing a trail technique with fellow cornerback Bradley Roby, who passed off his initial assignment to the deep safety on this side of the field, on top:

NFL Game Pass

The ability to play tight man-to-man coverage and communicate well in the backfield is something the Patriots did very well this season so far, and will likely be key when it comes to playing against Allen on Sunday. Having Gilmore on the star wideout for most of the day might be the best course of action, therefore. With one exception, New England’s number one has generally played well this year no matter who he lined up against and in which position.

Gilmore played both on the left and the right during the regular season, both on the slot and on the boundary. If he is picked to as the primary player to go up against Allen, he would likely have to do all those things as well but still would not be out of his comfort zone. And even though the Patriots often use their number two guy with safety help on top versus a top flight receiver, Allen might command Gilmore instead of undrafted rookie J.C. Jackson playing in his first postseason game.

After all, Gilmore is a much more experienced player and has shown an ability to stick with sound router runners like Allen — something Jackson at times still has issues with. He also has the length to compete on jump balls or otherwise contested catches against the 6’2, 210 lbs pass catcher. That all being said, using Gilmore exclusively on Allen might not be something we will see — at least when going by last year’s Patriots-Chargers meeting.

Gilmore sat the game out due to a concussion and was replaced in the lineup by Johnson Bademosi, who saw a lot of Allen. Overall, Allen was Bademosi’s primary assignment on 11 snaps — and on five of those, Philip Rivers decided to try him. The wideout caught three of the targets for 43 yards while also drawing one 30-yard pass interference penalty. Allen himself also interfered on one pass.

Bademosi was not the only player to be matched up against Allen, as fellow perimeter cornerback Malcolm Butler also was in coverage on eight occasions. Rivers, however, never went Allen’s way when going against Butler. New England’s safeties covered the wide receiver a combined six times, with zone or pass-off concepts being used on five occasions, and linebackers also covering twice.

What New England did last year against Allen was use different styles of defense depending on where he lined up. When on the perimeter, the cornerbacks would often play press-man one-on-one coverage — similar to what the Broncos also did earlier this year — with safety help over the top especially in Bademosi’s case. When Allen lined up in the slot, the Patriots used a different approach.

Strong safety Patrick Chung mostly lined up across Allen and either stuck with him in a trail technique with a safety over the top, or passed him off to a deep field defender like Devin McCourty or Duron Harmon altogether.

NFL Game Pass

On this two-point conversion play in the fourth quarter, New England used this very approach. Allen was lining up in the right-side slot, with Chung across and quickly starting to trail. Weak side safety Duron Harmon picked him up to clog the passing lane and force Rivers to look elsewhere on the ultimately unsuccessful attempt. In general, the plan worked well for the Patriots: Allen caught just for passes for 61 yards — most of which against Stephon Gilmore’s replacement, Johnson Bademosi.

That day, Bademosi exclusively lined up on the defensive right side with Butler playing opposite him. Defending the Chargers (or any other team) like that is nothing out of the ordinary, as the Kansas City Chiefs and Baltimore Ravens also did it this year. Both times, the defenses were relatively successful when it came to limiting Allen’s impact on the contest as a whole. And both times, bracket coverage like the Patriots’ last year played a big part.

Ultimately, New England could opt to go with the same plan on Sunday: have Gilmore lock down one side of the field with J.C. Jackson opposite him and Jason McCourty in the slot. However, as outlined above, it might be better to actually move Gilmore around more often to get the best matchups with the All-Pro on Allen, Jackson on Mike Williams, and McCourty on number three Tyrell Williams.

The Patriots used a similar plan against the Minnesota Vikings in week 13, when Gilmore followed Stefon Diggs around for most of the day. Going against a similarly talented offense — albeit one with a far better quarterback — it would not be a surprise to see New England go that route once more.