(image stolen from SB Nation)
Before this play running back Shane Vereen (circled) declared himself as an ineligible receiver to the referee, who told the defensive captain. As an ineligible receiver, Vereen can't go downfield, so he runs backward instead. Tight end Michael Hoomanawanui, aligned where the offensive left tackle would normally be, sprints down the seam uncovered by the surprised defense. The result is a fifteen yard pass from Tom Brady and a first down.
Ravens coach John Harbaugh was none too pleased. Calling the play and the preceding substitution "clearly deceptive," he insinuated that the referees did not understand what had happened, and that the NFL may change some rules in the offseason to prevent this kind of thing happening in the future. He even took an intentional penalty to prevent the Patriots from doing it on one play.
There is nothing illegal about what the Patriots did. Only those players who align in the backfield or as one of the two end men on the line of scrimmage are eligible to catch a pass; the five "covered linemen" are not. (On this play, Vereen is "covered" by Julian Edelman at the bottom of the screen, so he is aligned as an ineligible receiver, while Hoomanawanui is the end man on the left of the formation, so he is eligible.) In the NFL, the offense normally has five players with ineligible numbers (50-79) on the field, to help the referees identify who can and can't catch a pass. If they align with more or fewer than five such numbers, they must tell the referee who is or isn't eligible.
At first glance, this looks similar to plays you see from time to time where the offense uses an unbalanced formation to put a tackle out wide and hide a tight end at the tackle spot (LSU, Alabama, and Auburn have all done this recently). But there's a critical difference. On those plays, the offense still has the usual five ineligible numbers on the field, albeit in unfamiliar places. On this play, there were seven players on the Patriots offense (counting Brady) with jersey numbers indicating they could catch a forward pass. Vereen declared himself ineligible, just like when an extra offensive lineman comes on the field and declares himself eligible. But when one lineman declares himself eligible, the defense can find him easily. It's somewhat harder when a player reports as ineligible, leaving just a few seconds to determine by elimination the remaining five players who are eligible. This is what got Harbaugh so worked up.
Belichick explained the formation this way after the game: "We ran it three times, a couple different looks. We had six eligible receivers on the field, but only five were eligible. The one who was ineligible reported that he was ineligible. No different than on the punt team or a situation like that." Actually, when you put it that way, that sounds kinda familiar...
The A-11 offense was a short-lived high school offense based around a similar premise. This scheme (the name is short for "all eleven eligible") used a spread formation with three groups (called "pods") of three linemen each, with two backs in the backfield side by side, all of them wearing the jersey numbers of eligible receivers.
(image from Wikipedia)
Before the snap, all players except the center would stand in the backfield. Just before the snap, six of the players would step onto the line of scrimmage, "covering" five of them and making them ineligible receivers. After the required one second, the ball would be snapped and the five eligible receivers would be free to go downfield, with the other five staying near the line. Without enough time to adjust to the shift, the defense would often leave receivers running uncovered, just like Hoomanawanui.
|(image from fishduck.com)|
Normally, it wouldn't be legal to have eleven players on the field in eligible receiver numbers in a high school game. But the A-11 creators took advantage of a loophole, the "scrimmage kick exemption." Because the quarterbacks in the backfield were at least seven yards off the line of scrimmage, the A-11 was technically a kicking formation. And because high school teams often use defensive players on kick coverage units, it makes sense that there was a rule relaxing the normal regulations around eligible receiver numbers on kicking downs. But after two years of the A-11 turning the game upside down, the traditionalists had seen enough, and the National Federation of High School Associations voted in 2009 to close the loophole, restricting the scrimmage kick exemption to fourth downs. (In the NCAA the exemption exists only on obvious kicking situations, presumably fourth downs or late in the half.) The A-11 still exists as a (relatively) conventional unbalanced line formation, but the dream of "all eleven" football is dead, at least until fourth down.
But now, it looks like the Patriots may have resurrected it with their "punt team" offense. The NFL is the only league that allows players to declare themselves eligible or ineligible. Theoretically, there is nothing stopping the Patriots from going into their game with the Colts next weekend with eligible numbers on all of their players. Before the snap, five of the players could inform the referee that they are ineligible, then scramble to the line and snap the ball.
The creators of the A-11 hoped to change the game, but they couldn't overcome the powerful interests who wanted to keep it as it was. Time will tell if the Patriots are powerful enough to succeed where they failed.