Bears offensive tackle Bradley Sowell celebrates his touchdown catch against the Rams in December, which came on a trick play. (Joe Robbins/Getty Images)

On the first play of his head coaching career, Matt Nagy called “Papa Bear Left.” Back on the opening Sunday night of this NFL season, the Chicago Bears lined up in a T formation, with three running backs in a line behind quarterback Mitchell Trubisky, a relic from the days of leather helmets and George Halas. Before the touchdown drive finished, offensive tackle Charles Leno had lined up as a wide receiver.

Nagy did not stop proving himself capable of any trick, gadget or wrinkle. The Bears forced overtime against the New York Giants when running back Tarik Cohen threw a touchdown pass on fourth and goal. Backup offensive tackle Bradley Sowell caught a touchdown pass out of a formation that included only Trubisky, offensive linemen and defensive linemen. Defensive tackle Akiem Hicks ran in a touchdown.

Nagy and the Bears occupied the extreme end of a mini-craze this NFL season that could become a major factor in the playoffs, which begin Saturday afternoon. Trick plays — or what were once considered trick plays — and other offensive oddities became so prevalent that they started to seem not like tricks at all, but rather a normal part of NFL offenses. In a season overflowing with offensive creativity, strange is the new normal.

“I think if you just stay vanilla and you just try to continue to run the same things over and over again, eventually defenses will figure it out and they’ll stop it,” Nagy told reporters this season. “Adding some creativity to it, some misdirection and doing multiple things from it, it’s hard. It’s hard to defend. So you’ve got to always try to stay one step ahead of these defensive coordinators.”

How important might a trick play be in this year’s playoffs? Last postseason, famously, the Super Bowl hinged on one. Philadelphia Eagles quarterback Nick Foles asked Coach Doug Pederson if he wanted to run “Philly Philly” on fourth and goal from the 1-yard line. On the play, also referred to as “Philly Special,” Foles lined up in the shotgun with running back Corey Clement directly behind him. Foles walked to the right of the formation, pretending to call an audible. Clement took a direct snap, and Foles leaked to the flat as Clement ran left and flipped the ball to tight end Trey Burton, who was sprinting back to the right. Burton tossed a pass to Foles to push the Eagles ahead of the Patriots by 10 points just before halftime for a critical score in Philadelphia’s championship victory.

This season, Cleveland Browns quarterback Baker Mayfield caught a two-point conversion pass on a nearly identical play. Afterward, as if to underscore the spread of trick plays, Mayfield pointed out that he had scored a touchdown on the play at Oklahoma before the Eagles pulled it off in the Super Bowl.

“Philly Philly” launched a new inclination for trickeration. This season, not counting fake punts, 24 non-quarterbacks attempted a pass, and nine of them threw touchdown passes — including Giants wideout Odell Beckham Jr., who threw two. Last year, 13 non-quarterbacks threw passes and just two of them went for touchdowns. And there were 117 players other than quarterbacks and running backs who rushed the ball this year, compared with 93 last season.

While true trick plays remain a small portion of every offense — teams ran trick plays on 6 percent of their snaps in both 2017 and 2018, according to George Chahrouri, director of research and development for Pro Football Focus — they have been more successful this year, converting at a 47 percent rate after last season’s 43 percent. Perhaps more significantly, coaches have embraced plays that approach the line separating standard play from gadget. CBS Sports analyst Bruce Arians, formerly the Arizona Cardinals’ head coach, noticed an increase in plays that years ago would have been decried as gimmicks.

“It’s the norm,” he said. “It’s been building the last four years.”

Throughout his entire career, spent mostly as a defensive coordinator, Browns interim coach Gregg Williams viewed an offense running a trick play as a compliment. It meant the opponent couldn’t score against or overpower his defense, so it had to resort to the unconventional. But this season, that changed. Planning for trick plays is “just part of our league right now,” Williams said, “and we have to do it, week in and week out.”

Arians connected the upswing in trick plays to the skyrocketing frequency of pre-snap motion and the connected widespread adoption of fly sweeps, when a wide receiver sprinting across the formation takes a handoff from the quarterback. The play had been consigned to the college ranks before Andy Reid and Sean McVay made it an NFL staple.

The prevalence of those plays increases both the benefit and the opportunity for a wide receiver to throw a pass. Put one such play on film, and it forces opposing defensive backs to honor wide receivers down the field, making it more difficult for them to stop the fly sweep. Before the Ravens played the Browns in Week 17, Baltimore defensive coordinator Don Martindale noted that he knew Cleveland wide receiver Jarvis Landry throws left-handed.

Behind McVay, the Los Angeles Rams remain the team most reliant on fly sweeps. Rams wideouts Robert Woods and Brandin Cooks combined for 29 carries this season, and the benefit shows up even when they do not get the ball. The Rams use motion on almost every play, and it makes the simplest designs more effective.

“The team that does it the best is the Rams,” Arians said. “They fly motion and jet motion almost every play, and then they just hand the ball to [running back Todd] Gurley. It distracts the linebackers’ eyes. It affects their vision and their concentration.”

Making trick plays, or something close to them, a standard part of the offense rather than an outlier can enhance an entire system. On one play in Week 17, the Bears sent the same wide receiver in motion behind Trubisky four times before they ran a simple rollout pass to the right — away from where the receiver eventually ended up. According to Sports Illustrated, the play is called “Lollipop,” borrowed from Nagy’s time under Reid in Kansas City.

“If they don’t have a ‘why’ to them, and you’re just doing it to show that you’re trying to be creative, that doesn’t mean anything,” Nagy told reporters this season.

Despite their increase and frequent success, in some corners trick plays are still viewed with derision. In answering a question about the number of trick plays he has seen this season, Williams went out of his way to make clear that he calls them “gimmick plays.”

“If you play the right technique and the right fundamentals and stick with your assignments, trick plays shouldn’t affect you,” Martindale said. “If somebody gains five yards on a reverse, that’s not a big play in my eyes. It’s second and five; let’s go.”

Most respected offensive coaches have leaned on them. New Orleans Saints Coach Sean Payton has frequently aligned Drew Brees as a wide receiver to use third-string quarterback (and bruising runner) Taysom Hill on exotic plays. One formation featured no quarterback until Hill came in motion and lined up in the shotgun.

Colts Coach Frank Reich, who helped install “Philly Philly” as the Eagles’ offensive coordinator last season, called a third-and-one pass to quarterback Andrew Luck out of a wildcat formation. At the goal line, he used tight end Eric Ebron on an end-around that resulted in a touchdown.

More teams have embraced the potential mental advantage of executing a trick play. Nagy has said that he likes to use offbeat personnel because of how excited teammates get watching linemen or defensive players touch the ball. The plays engage the team during lulls in practices and catalyze it during games.

“I mean, how many linemen score in their lifetime?” Giants Coach Pat Shurmur said. “How many receivers have ever thrown touchdown passes? The bigger view of this is, at the time of the game when you need a little spark, it kind of gives you a little emotional boost.”

It could also, in the right circumstances, win you a Super Bowl. And even if a trick play doesn’t play such a significant role this postseason, it’s safe to assume that defensive coaches will be studying which hand opposing wide receivers throw with.

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