The worst part about playing against Aaron Rodgers is the dread. Opponents forever wonder how the Green Bay Packers quarterback is going to beat them this time. Will it be a pass fired on the run? A lob over the linebacker’s head? A Hail Mary heaved high into the sky?

Redskins linebacker Mason Foster has a story. Back in 2011, his Tampa Bay Buccaneers went to Green Bay to play the Packers, who were 10-0 at the time. For three quarters, the Bucs held close, trailing only 21-19. They thought they might win.

“Then on one drive, [Rodgers] just picked up on something, went up-tempo and just went crazy for the rest of the game,” Foster says. “He just figured it out, was calling out the blitzes, calling out all the looks and just went up and down the field on us.”

Tampa Bay lost 35-26.

But here’s the thing about that game: Foster remembers the Bucs being up 21-0 at the moment Rodgers tore them apart. In fact, he is certain of it.

But who can blame Foster for thinking Rodgers had led the Packers back from three touchdowns down that day? Rodgers has led so many comebacks and crushed so many dreams they become a part of opponents’ memories, making players believe it has happened to them, too. Two weeks ago, he was knocked from the Packers’ opening game with a knee injury that required him to be carted to the locker room, only to hobble back in the second half with Green Bay down 20-3 and lead the Packers to a 24-23 victory. It was the 13th fourth-quarter comeback of his career.

On Sunday, the Redskins will face Rodgers and the Packers at FedEx Field in Landover, Maryland. For a team that lost last week after giving up three 75-yard touchdown drives to the Colts and quarterback Andrew Luck, the thought of playing Rodgers can’t be a good one.

“He does so many things that are unscripted,” says former Cardinals coach Bruce Arians, now an analyst for the NFL on CBS.

There is no real way to prepare for Rodgers. Meticulously designed schemes become useless because eventually he figures them out. Before each snap, he stands behind his line, scanning the defense for hints of what might be coming. Those who play against him have learned to reveal nothing about their intent, disguising formations for as long as they can, all in the desperate hope of somehow fooling him.

“If you show at the start that you are coming with the blitz, you are dead,” says former Redskins linebacker London Fletcher, who, like Arians, is an analyst for the NFL on CBS.

Even if Rodgers doesn’t recognize the defense, he can beat it with his voice. Opposing players say his cadence is impossible to judge. He might not wave his arms or shout “Omaha!” like Peyton Manning, but the small jerks of the head and strange vocal inflections are impossible to interpret.

Because most agree the best way to beat Rodgers is to send an aggressive pass rush up the middle, putting big hands in his face, pass rushers and defensive linemen are especially anxious to jump at the snap of the ball. Rodgers plays to their impatience, changing the sound of his voice with what seems like each snap. Deciphering his hard count is close to impossible. Sooner or later, someone is going to jump.

“He’ll go ‘huthut!’ and it’s ‘oh, shoot,’” Fletcher says with a laugh.

The best thing to do when this happens, Fletcher says, is to keep coming and be absolutely sure to tackle him. There is nothing the Packers quarterback loves to do more than lure defenses offsides, drawing a penalty and essentially earning a free play. Almost always, he will throw deep, realizing there is no loss in aiming for the end zone. If he completes the pass, Green Bay can decline the penalty. If it’s incomplete or intercepted, the Packers can take the call and keep moving.

“He has all the tricks in the book,” Foster says.

Once the ball is snapped, there’s no knowing what Rodgers might do. Arians says that even though Rodgers is not a runner, teams have to treat like one because he is so elusive inside and outside the pocket. Players like this are particularly challenging for defenses since they stymie pass rushes, making hit harder to get sacks or force quarterbacks into frantic, hurried throws.

There has been a lot of talk this week about Rodgers’ injured knee, leading many commentators and Redskins fans to believe the quarterback who comes to FedEx Field will be somehow diminished, unable to move and vulnerable to Washington’s pass rush. Rodgers himself has fueled some of this speculation by wearing an enormous brace on his knee in last Sunday’s tie with Minnesota and openly worrying that playing on the knee might make the injury worse.

Fletcher scoffs at the idea of a hobbled Rodgers, saying: “I’ve played on multiple MCL sprains, the knee loosens up as the game goes on. He can just play with a wrap on his knee and be fine.”

Given the 281 yards for which Rodgers threw against the Vikings on Sunday, while moving robotically around the field, Fletcher’s sense is probably right. There’s no such thing as a diminished Rodgers. Not as long as he is able to throw.

“A cannon,” is what Washington safety D.J. Swearinger calls Rodgers’ arm.

In the end, teams probably fear Rodgers’ throwing ability more than anything else. Coaches like to talk about quarterbacks “making all the throws,” as in being able to complete passes to all levels of the field. Most NFL quarterbacks can “make all the throws” at some level, usually excelling at a few of those passes.

Rodgers, those who have played against him marvel, can make every throw.

Really. Every throw.

“The big thing is he makes them accurately,” Arians says.

“He squeezes it in there,” says Foster.

“Whether he’s on the run or he’s falling back or he’s throwing it downfield, throwing it short. It doesn’t matter,” Swearinger says, shaking his head. “He’s always accurate.”

Fletcher sighs. “Nobody else can make those throws,” he says.

And yet it’s not just that Rodgers can make all the throws it’s that he throws his passes hard. Very hard.

“You just see it, it’s a faster ball than anyone else,” Swearinger says.

Fletcher has a Rodgers pass in his mind, one he saw the quarterback make in a game against the Redskins years ago. Evading a rush, Rodgers turned to his left and started running toward the sideline. Then, while still running, he fired a pass into a receiver’s arms at a velocity that still has Fletcher trying to figure out the physics of such a throw.

“Think about that, he’s right-handed and he’s running to his left,” Fletcher says. “That’s a hard throw to make because you are running and you have to turn your shoulders to make the throw. But he doesn’t turn his shoulders, he just throws it.”

One would think that if Rodgers is throwing harder than any other quarterback in football while running from side-to-side or falling backward that his passes would be difficult to grab. But his 65 percent completion percentage is seventh-best in NFL history and his 103.9 passer rating is the best ever according to the statistics website Pro Football Reference.

“Some guys’ passes are like rocks,” Arians says. “Some are like marshmallows. He throws marshmallows, but with a lot of speed.”

“It’s a zip, but it’s always a spiral,” Swearinger says.

Then, just in case Rodgers hasn’t already won by deciphering the defense, or drawing pass rushers offsides, or throwing speedy marshmallows into his receivers’ hands, he has one last trick: The Hail Mary. Three times in the last three years, Rodgers has won or tied games with long, desperation heaves.

“But I’ll tell you what,” Swearinger said, “I’m approaching this like it’s one of the biggest games of my career. You got the best quarterback or one of the best quarterbacks in football, and you got to approach it like a Super Bowl.”

“There’s definitely only one of him,” Swearinger adds. “No. 12 is a different species.”

Which is enough for anyone to dread playing against.

les.capenter@washpost.com

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