Defensive line coach Chris Wilson had a message for his room last week as the team's mandatory minicamp ended, and he wanted to make sure he gave the message loud and clear: "I told them," he said, "that the No. 1 thing is that playing great defense starts up front. As we go up front, we go defensively."

Having a happy Fletcher Cox sure helps everyone "go" up front for this football team. The new six-year contract extension the Eagles announced with Cox on Monday is a huge win for both sides and a very significant accomplishment for both the player and the front office. In a rapidly changing sea of contracts and guaranteed dollars, the Eagles and their All-Pro defensive lineman -- who can play inside at tackle as well as line up on the edge in certain situations if the matchup is right -- came to terms without any acrimony, without any public debate and with nothing but respect and admiration.

Cox, a player whom the Eagles traded up to draft in 2012, has been an impact player from the moment he became an Eagle and he's gotten better and better even when the Eagles moved to a 3-4, two-gapping front that required him to have responsibility for the gap on both sides of an offensive lineman. Now the Eagles are in a 4-3 front and defensive coordinator Jim Schwartz wants his linemen to get up the field quickly, get off the ball with alacrity and a physical presence. 

Cox is the perfect fit to dominate up front after his breakout 2015 when he was named a second-team All-Pro by The Associated Press, made his first Pro Bowl and was voted by his teammates as the Eagles' recipient of the Ed Block Courage Award. Cox set career numbers with 9.5 quarterback sacks and 104 tackles. He also topped the Eagles with 16.5 tackles for loss, 32 quarterback hurries and three forced fumbles.

Not a bad season for Cox, right?

His upward trajectory continues and is, in football talk, limitless.

"Fletcher is a special player who has not only the ability to be the kind of player that he has become, but also the desire and the work ethic," said Wilson, who coached Cox for two seasons at Mississippi State before Cox declared for the NFL Draft after his junior season there. "He is a great teammate with a high football IQ and he does everything you could want as a defensive line coach. It's a pleasure coaching Fletcher."

Cox missed the voluntary portion of the offseason workouts, but attended last week's mandatory camp. He issued a statement and then spoke to the media during the week and was reserved in his comments as the negotiations were ongoing behind the scenes. Clearly, his representatives and the Eagles, led by Howie Roseman, were very precise in their dealings to sew up such a monstrous contract.

"I'm just glad he's back and it's good seeing him. He means a lot to this defense and what we're trying to do," defensive tackle Bennie Logan said. "We're going to have some fun up front this year."

The key to Schwartz's "attack-and-react" defense is that the Eagles win the line of scrimmage and that the linemen penetrate the offensive line and get into the backfield and cause some major problems. Schwartz, of course, has had great success in Tennessee and Detroit and Buffalo, in large part because the defenses there had playmakers at the line of scrimmage. 

Cox is the dominating playmaker here, and now he's got all of the business side of football happily done, so when he reports to the NovaCare Complex for Training Camp in late July he's going to be a happy and focused man.

Let's give Roseman and his team some credit here for being so upbeat and complimentary these many months when asked about Cox and the state of the negotiations. Roseman always said the same thing: He was confident that a deal was going to get done and he expected Cox to be an Eagles for a long, long time.

Now Cox is in the fold.

Wilson thinks he has a defensive front with two-deep depth, knowing that Cox and Logan headline the tackle situation, with players like Beau Allen, Taylor Hart and Mike Martin battling for playing time behind the projected starters.

"I like very much what we have there," Wilson said. "I see a lot of competition. We had a great spring. I'm really excited about our situation up front and the way the players have accepted what I'm teaching them. We're going to get after it in camp. I can tell you it's going to be an extremely competitive room. We need depth to make this work and we have it both inside and on the edge. 

"Our responsibility is to take over the line of scrimmage. The players know it and they embrace that challenge."

Having the Cox negotiation off the table -- and it was a whopper, very complicated and hugely important for the franchise -- makes everyone breathe just a little bit easier six weeks ahead of Training Camp. The Eagles have perhaps the best young defensive tackle in the league through 2022. Cox has his mega deal. In this case, both sides are the winners, and that's a great feeling to have. !

• PHOTOS: The Best Of DT Fletcher Cox
• VIDEO: Fletcher Cox Highlights
• READ: Cox Continues History Of Great D-Linemen
• READ: Ed Block Courage Award – Fletcher Cox
• VIDEO: NFL Top 100: Fletcher Cox
• VIDEO: Fletcher Cox – In The Fast Lane
• READ: Cox’s Humble Beginnings
• VIDEO: Fletcher Cox At The Pro Bowl