As much as we want to evaluate Fletcher Cox' get-off at the snap of the ball and Mychal Kendricks' athletic ability and the way Bryce Brown looks carrying the football, the coaches know that the mental side of the equation probably carries more weight this weekend.

The Eagles have five practices scheduled -- two on both Saturday and Sunday and one on Monday -- and they will have their 9-player draft class, most of their non-drafted free agents and some invited tryout players on the field for the work.

This is the first introduction to life in the NFL, and all that comes with it. The pace will be extremely fast for the rookies, mostly because the coaches want to let them know that to make it in the NFL, a player has to adjust and focus while moving 100 miles per hour. There is little slack given to mental errors; indeed, the test this weekend is to take what the coaches teach in the classroom and apply it on the field, at full speed.

What the coaches want to see is how fast the players get into the right positions on the field literally minutes after they are taught X's and O's.

I'm sure you are going to read about this player performed and about how that player stepped up, but the truth is that the grades are going to come from the coaches based more on mental ability rather than straight-line speed running a pass route against air.

This is a tease weekend for us, in other words. It is a primer for the players on what to expect in the months ahead ...

• I've talked to plenty of people about Brown, the team's seventh-round draft pick. He is an intriguing player. I admit I am fascinated, simply because he has a storied past -- he was a superstar player in high school and one of the most recruited players in the nation -- and because he is a 6-foot, 223-pound athletic freak. Brown has the athletic skills to be a top running back. That's why the Eagles drafted him rather than take the chance he would sign elsewhere as a free agent. Brown has always been bigger and stronger than the rest of the players on the field, so he has to show he has another gear and can run away from defenders. Of course, he also has to knock off the rust from minimal playing time in college and pick up blitzers and run precise routes, etc. Interesting guy.
• That said, I like Chris Polk a lot as a rookie free agent. He's got some wear and tear, though, so Polk has to stay healthy through training camp and make the most of his practice reps. The Eagles have a couple of nice prospects here, along with Dion Lewis, behind LeSean McCoy.
• What is so interesting to me about Nick Foles, officially listed at 6-6 and 243 pounds, is that he is so much different from what we have seen in the Andy Reid era at quarterback. Donovan McNabb, Jeff Garcia, Kevin Kolb (to a degree) and certainly Michael Vick move around the pocket and escape pressure and, for McNabb and Vick, put pressure on defenses with their legs as well as their arms. Foles has been described as someone with very good footwork in the pocket, but he is a threat to run? we're going to find out ...
• To me, anyway, Mike Kafka has the edge over Trent Edwards for the No. 2 job behind Vick. Kafka gets first crack at the job. But I like Edwards' work ethic, his demeanor, his body and the fact that he knows this is a second chance to really learn how to play the quarterback position with excellent coaching. In Edwards, Kafka and Foles, the Eagles have their most physically-imposing group of quarterbacks maybe ever.
• I have heard a lot of compliments paid toward Casey Matthews this offseason for the way he attacked the weight room and his conditioning following his rookie season. Matthews was coming off a shoulder injury when the Eagles drafted him and really couldn't hit the weights as he wanted. Now, we'll see. Does Matthews have a chance to move to the weak side to challenge Brian Rolle for the starting job?
• Marvin McNutt seems like a bigger Jason Avant to me. Let's see him at this level, of course, but he's 6-3 and he runs good routes and he has strong hands. Both McNutt and Mardy Gilyard are going to push for roster spots. That's how I see it at this stage.
• Can't say I know much about the offensive linemen drafted or signed recently, other than the Eagles are making sure they are as stocked as possible with depth behind their starters. I will put all the faith in the world in Howard Mudd. No worries there.
• Spent some time with linebacker DeMeco Ryans on Wednesday, who has to get used to all of this commotion about the team's Wide 9 alignment. "Once the ball is snapped," he says, "football is football." Agreed. We have all made too much of the Wide 9. Many teams use it to one degree or another. Juan Castillo varied it last year, with a lot of success. Having improved linebackers behind the defensive end playing the "9" technique, lined up three yards outside the right offensive tackle, is going to help the fans and the media understand that what Jim Washburn preaches isn't necessarily radical, but just good football coaching.
• The Eagles are in good shape signing their draft picks. That is not going to be a concern. After the draft class is signed, sealed and delivered, do the Eagles focus their attention on extending some contracts of some of their young veterans?