There is no secret that All-Pro wide receiver Calvin Johnson is the focal point of the Detroit Lions offense.

Last season, Johnson (a.k.a. Megatron) had 96 catches for 1,681 receiving yards and 16 touchdowns. The 6-5, 236-pound pass catcher is the total package. He's got height, speed, athleticism, route running ability, hands and, as cornerback Dominique Rodgers-Cromartie noted earlier in the week, attitude.

Through the first four games of 2012, Johnson leads the Lions with 29 catches for 423 yards and a touchdown. Even though defensive gameplans start and end with Johnson, he is still very productive. How the Eagles prepare for Johnson will make a huge difference in Sunday's game.

"You just have to frustrate him. You try to get into his head; get up there, put your hands on him and be physical with him and basically get in his head and frustrate him," Rodgers-Cromartie said. "You know he's going to get the ball, you know the ball is going to come out there a lot. If you can stop him from making a catch, they tend to get frustrated and tend to drop balls."

Teams don't have two Pro Bowl cornerbacks like Rodgers-Cromartie and Nnamdi Asomugha at their disposal. The Eagles also have two Pro Bowl pass rushers in Trent Cole and Jason Babin to affect the quarterback's timing and a Pro Bowl middle linebacker in DeMeco Ryans.

The Eagles faced a similar challenge with Cardinals wide receiver Larry Fitzgerald in Week 3. Fitzgerald had a season-high nine catches for 114 yards and a touchdown. Rodgers-Cromartie stayed on the left side of the field, Asomugha on the right side and rookie Brandon Boykin lined up in the slot.

Asomugha said that the Eagles learned from the Cardinals game.

"It was one of those things where, during the week, we had a way we were going to do it, and then we got closer to the game and we thought, we should probably just stay on our sides," Asomugha said.

"I think we learned from that a little bit. There will be different things that we do. It's not going to be a generic game plan. You're talking about one of the best receivers out there. Whatever we didn't do against Larry, I think we've learned from that."

In the past two games, the Eagles have had Rodgers-Cromartie shadow the opponent's better vertical threat. Asomugha tails the other team's more complete receiver from a route running standpoint. Boykin would face whomever lined up in the slot.

Last week against the Steelers, Rodgers-Cromartie battled wide receiver Mike Wallace because more of his routes were vertical. Asomugha took on Antonio Brown, who is quicker and runs more short and intermediate routes.

Here's one thing the Eagles have to take into consideration. According to Pro Football Focus, 21 of Johnson's 42 targets this season (50 percent) have come when he lined up in the slot. He has 14 catches for 248 yards out of the slot. If the Eagles keep Boykin in the slot against Johnson, it will be the fifth Pro Bowl receiver he's battled in his sixth career NFL game.

"I think it's helping him. It's going to mature him fast as a player," Rodgers-Cromartie said. "One thing I try to tell him, he comes in here and he asks me, 'How do my struggles just first coming in,' and you have to understand, it's your first year and you're playing the hardest position there is to play, and you're playing Pro Bowl-caliber guys. It's not like you're playing this guy or that guy. You're playing guys who have been doing it for years. I think it's given him a plus. He's learning more quickly."

Defensive coordinator Juan Castillo would not reveal the gameplan for covering Johnson. He simply said that he hopes after the game he's being told that it was a good gameplan. We're all just hours away from finding out.

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