Ravens experimenting with illegal formations

Ravens head coach John Harbaugh wasn't happy about the unique four-lineman formation used by the New England Patriots in their January playoff victory over Baltimore, saying afterward he felt it was deceptive.

Now, he's using some of those same tricks in his practice sessions.

"We are working on formations – legal formations, illegal formations, unexpected formations," Harbaugh told reporters Thursday after the Ravens wrapped up their minicamp, via For The Win.

"The first time we ran it, you heard (linebacker Terrell) Suggs out there saying, 'That's not legal, that's not legal.' We will not assume that the referees are going to understand or always get it right when a formation goes out on the field, so we're working on everything."

The Patriots' formation was deemed legal by the NFL at the time, but it did lead to the implementation of a new rule making it illegal for an offensive player wearing an eligible number to report as ineligible and line up outside the tackle box.