Calvin Johnson spent a lot of time this offseason working on the mental parts of his game after finishing 2012 with 1,964 yards.

Johnson has watched a lot of film and attempted to have a better understanding of what Matthew Stafford is thinking and planning.

"I'm just trying to see things as he sees them," Johnson said. "I'm running my route, I'm trying to be able to see spaces as he sees 'em so I can put myself in the right position.

"You can really get a lot from watching film and seeing the spaces. It's tough to see the spaces while you're running, compared to seeing 'em on the field. From that experience, you're able to develop (chemistry)."

Johnson and Stafford have worked together on figuring out how to beat defenses designed specifically for him.

"Defenses definitely have made it tough, especially when I'm on the outside," he said. "They can double me, they can bring the safety on top and just kind of take you out of the quarterback's read all together."