There's a trend in listening to what opponents have to say about the Ravens defense.
One word that comes up often is "scheme."
The man in charge of the Ravens' scheme, the man who manages it on gameday, is Defensive Coordinator Dean Pees.
In his fifth year as the Ravens' defensive play caller, Pees will bring his top-ranked defense north to Foxboro for a Monday Night Football meeting against his former employer. Pees spent six seasons in New England (2004-2009), including four as defensive coordinator.
Pees downplayed the significance of facing his former team, but his importance in the Ravens' No. 1-ranking was not downplayed by his players.
Outside linebacker Terrell Suggs said Pees is "playing at an all-time high."
"He calls all of our plays, he's the one up there orchestrating everything we do," cornerback Jimmy Smith added. "He's been excellent this season, as far as mixing it up, pressuring. We sit atop the league right now because of the things he's been doing."
Pees left New England after the 2009 season to become the Ravens' linebackers coach. It was a step backwards in title, but Pees was ready for a change.
Two years later, Pees took over as the Ravens' defensive coordinator after Chuck Pagano left to be the head coach of the Indianapolis Colts. Pagano, just like Rex Ryan before him, was beloved by his players.
Pees has also gained the respect of his players, who describe him as a well-prepared, players coach.
"The thing I admire about Coach Pees is he covers everything. Even if there are 'what ifs,' he's already thought about that 'what if,'" Smith said.
Smith recalled a time three years ago when playing against the Pittsburgh Steelers that the defense was caught off guard by a big-bodied package the Steelers used.
"From that day on, coach has never not put in a package. He leaves no stone unturned," Smith said. "He's been coaching for longer than my older brother's been alive. I think he's been coaching for 36 years. I don't think there's a play he hasn't seen or a formation."
The Patriots tested the* *Ravens defense in their last meeting in the 2014 divisional playoffs.
They used a loophole in the NFL rulebook to run a trick formation twice to pick up big yardage. The Patriots also used a trick play on a backwards pass to receiver Danny Amendola, who threw to receiver Julian Edelman for a 51-yard touchdown that erased Baltimore's second 14-point lead.
But the Ravens have a more disciplined defense this year, and that starts with coaching.
"We bought into the system," linebacker C.J. Mosley said. "Coach Pees said we were going to keep it simple and stick to the basics when we run our blitzes and coverages. And he's stuck to that."
While keeping things simple, Pees is also the master of disguise for opposing offenses. Patriots Head Coach Bill Belichick, a defensive-minded coach himself, said Pees does a "good job of keeping you off-balance."
The Ravens have spent a lot of time coaching safeties Eric Weddle and Lardarius Webb on masking coverages. They also mix up their defensive front's alignment, and have an intricate blitz package.
"They're not going to sit there in one thing all day," Belichick said. "They've never done that. They're going to change up the looks on you."
"Coach Pees puts guys in great positions to make plays," Mosley said. "When we get our blitz package going, we've got a lot of different ways to get to the quarterback and show different things."
Pees will be playing chess this Monday night. He said the most meaningful part of the game is that the Ravens are in first place in the division and need a win to stay there, but there's no denying that there's still something different about facing the Patriots for Pees.
This certainly won't be the first time Pees has squared off against his former team, but he said it's still like playing against your brother in golf.
"Sometimes you want to beat your friends and your family more than you want to beat somebody you don't know," Pees said
"It's just like a player playing against their old team," Mosley added. "I'm pretty sure if he goes home with a win, he'll celebrate a little bit."
