Mathis: 'Very confident' Lions can succeed without Suh

They lost the best player from the league's No. 2-ranked defense, but Rashean Mathis has no doubt that the Detroit Lions can repeat their success this fall.

"I'm very confident," Mathis said in a teleconference with Detroit reporters today. "I'm very confident in the guys who we have. I'm also confident in our personnel department in getting people in here to help us, and that's what the NFL is all about.

"You're always going to lose someone. There's no defense or no offense that has stayed the same as you look around the league. There's big, key pieces missing in a lot of places, and that's what makes this the greatest game, because you're able to plug in and you're able to move on and see how well you're able to adapt to new players and new players are able to adapt to a new scheme."

The Lions lost starting defensive tackles Ndamukong Suh and Nick Fairley in free agency but return their other nine starters from a defense that yielded the second-fewest yards and third-fewest points in the NFL last year.

Haloti Ngata and Tyrunn Walker will replace Suh and Fairley, with more help perhaps on the way through the NFL draft. And on Wednesday, the Lions re-signed Mathis, their last remaining key free agent, to a two-year, $3.5-million contract.

Mathis said the key to replacing Suh, a three-time all-pro, is "having someone plug in that gap." The Lions are hoping Ngata, whom they acquired in a trade from the Baltimore Ravens, can approximate Suh's production on the field.

"That's always the key," Mathis said. "In any business field, regardless whether it's sports or not, if you lose a big key piece of what made you successful. Having someone step up and plug in that gap, that'll be the only way that you're able to be successful as you were before, having someone step up. That's just the nature of the game."

While the Lions will have one of the older defenses in the league next year -- including Mathis, who turns 35 in August, 30-year-old Stephen Tulloch and 31-year-olds Ngata and safety James Ihedigbo -- they're also counting on gains from young players Ziggy Ansah and Darius Slay.

Mathis said one reason he wanted to return to Detroit -- if he didn't re-sign with the Lions, he planned to retire -- was to continue working with Slay, who was the team's most improved player last year.

"I expect better (from Slay this year)," Mathis said. "There's always room for improvement -- he knows that, and that's something that I harp on. So room for improvement is always key. This will be my 13th year, and I still have room to improve, so it never stops. It never stops. Life doesn't stop for anyone, so you're either getting better or you're getting worse; there's no staying the same."

Contact Dave Birkett at dbirkett@freepress.com. Follow him on Twitter @davebirkett.