The Patriots dug into their bag of tricks on their second drive of the third quarter, lining up just four offensive linemen and declaring a normally eligible receiver as ineligible to keep Baltimore off balance.
Ravens players were confused about which Patriots to match up with in coverage, and Harbaugh drew an unportsmanlike conduct penalty for running onto the field and screaming in objection. Harbaugh said after the game that the officials "didn't understand what was going on."
"We wanted an opportunity to be able to ID who the eligible players were," Harbaugh said. "What [the Patriots] were doing was they announce the ineligible player and then Tom [Brady] would take them to the line right away and snap the ball before we had a chance to figure out who was lined up where. That was the deception part of it. It was clearly deception.
"So the officials told me after that they would give us the opportunity to do that, which they probably should've done during that series but they didn't really understand what was happening. That's why I had to take the penalty, to get their attention so they would understand what was going on because they didn't understand what was going on. ... That's why guys were open, because we didn't ID where the eligible receivers were at."
Brady disagreed with Harbaugh's description of it as an act of deception.
"I don't know what's deceiving about that," he said.
When informed of Harbaugh's objection, Brady fired back.
"Maybe those guys gotta study the rulebook and figure it out," he said. "We obviously knew what we were doing and we made some pretty important plays. It was a real good weapon for us."
Patriots coach Bill Belichick explained the strategy, which he utilized on three plays and featured four offensive linemen on the field and had either running back Shane Vereen or tight end Michael Hoomanawanui lined up as ineligible.
"It's a play that we thought would work," Belichick said. "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."
Harbaugh said it was a tactic that "nobody has ever seen before." When asked whether he thought it was cheap or dirty, he said he would not comment.
"The league will look at that type of thing, and I'm sure that they'll make some adjustments and things like that," Harbaugh said.
Patriots offensive coordinator Josh McDaniels pulled out the trickery when his team was down by 14 points and the offense had gone three-and-out on the opening drive of the third quarter. The drive resulted in a 5-yard touchdown pass to tight end Rob Gronkowski and frazzled the Ravens' defense.
"There was a lot to the plays," Hoomanawanui said. "I have to report as ineligible. I can't go down the field. I can only block. So as hard as it is for them to figure out, there's a lot that goes into it on our side, too.
"You could see how frustrated they were on who to cover and this and that, so it turned out to be great plays for us."
Patriots right guard Ryan Wendell, who shifted to center after rookie center Bryan Stork left the game with a knee injury, couldn't recall any game he played in where anyone only used four offensive linemen.
"I think it just says that it's the playoffs and we are willing to do whatever it takes to win," Wendell said. "There's no good in holding anything back right now."
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