When Bill Belichick pulled something new from his bag of tricks last week, some wondered if the three-time Super Bowl champion coach had found another way to bend the rules.
The New England Patriots were creative and intentionally deceptive, but using four offensive linemen isn't illegal.
The tactic worked and angered the Ravens and coach John Harbaugh. There's no telling what wrinkles Belichick and the Patriots (13-4) are planning for Sunday's AFC championship game against Indianapolis (13-5).
''It's a situation that I saw another team use, kind of,'' Belichick said, explaining the unique formation. ''Then we talked about it and thought about ways maybe to put some pressure on the defense with that concept of having more receivers on the field than were actually eligible. To make them ineligible instead of making an ineligible guy eligible, to go the other way around. We came up with a few ideas.''
OK, here's a simple summary of what the Patriots did for three plays against Baltimore:
(asterisk) Right guard Josh Kline came off the field.
(asterisk) Backup tight end Michael Hoomanawanui entered and lined up where the left tackle traditionally plays but declared himself eligible.
(asterisk) Left tackle Nate Solder moved inside to left guard.
(asterisk) Running back Shane Vereen entered and lined up in the slot, but was technically the right tackle and therefore ineligible.
That created confusion because the defense covered Vereen, thinking he was going to run a pattern. Hoomanawanui was allowed to run freely down the seam.
Hoomanawanui caught two passes for 16 yards and 14 yards Harbaugh drew an unsportsmanlike penalty for going on the field to argue that his defense should've had more time to identify eligible receivers before the snap.
After the penalty, Tom Brady tossed a touchdown pass to Rob Gronkowski to cut the Ravens' lead to 28-21.
''Nobody's ever seen that before,'' Harbaugh said. ''It's not something anybody's ever done before.''
Belichick said he expanded on another NFL's coach's idea, but didn't say who it was. Philadelphia's Chip Kelly is known for his innovative strategies and he introduced a few of these formations right away in his first game in 2013.
Kelly has used a three-man line with tackles Jason Peters and Lane Johnson both split wide to opposite sides. He's used a formation where both tackles are on the same side. And, he's had Johnson line up in the slot.
Kelly and Belichick are good friends and the Eagles and Patriots have practiced against each other the week leading up to their preseason games each of the last two seasons. Maybe they shared secrets.
Oregon, Kelly's former team, uses strange formations often, especially on extra-point attempts.
The Detroit Lions ran a similar play in Week 6 where they lined up six offensive linemen with one of them split wide. It didn't work and Matthew Stafford was sacked on the play.
Perhaps Belichick and offensive coordinator Josh McDaniels watched the Alabama-LSU game on Nov. 8. The Crimson Tide ran the same formation on the first play of overtime and 304-pound offensive lineman Brandon Greene caught a 24-yard pass to the 1. Greene lined up in the same spot the Patriots put Hoomanawanui.
''Hardly ever see only four offensive linemen in the game,'' former NFL quarterback Brady Quinn told the AP this week. ''And to put an ineligible player who wears an eligible number out at a wide receiver position is unique. On top of that, the play was well-designed where Vereen stepped back and acted like he was running a screen. Nothing illegal about it.''
Earlier last week, Hall of Fame coach Don Shula referred to Belichick as ''Beli-cheat'' in an interview. That's a label Belichick has heard since the coach was fined $500,000 and the Patriots were fined $250,000 and stripped of their 2008 first-round draft choice by the NFL for videotaping New York Jets signals during a 2007 game.
But trick plays aren't cheating or even unusual. The Patriots tied the score later in the game on wide receiver Julian Edelman's 51-yard TD pass to Danny Amendola.
Belichick doesn't expect anything to prevent the Patriots from using their new formation against the Colts.
''I'd venture to say I couldn't remember the last time that I haven't seen an eligible receiver report as an ineligible player in the NFL,'' Belichick said. ''I would say it happens in every game on the punt team. You're allowed to do that. We did it.''
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