INDIANAPOLIS (AP) -- Colts linebacker Bjoern Werner understands the mission.
He must replace Robert Mathis, the defending NFL sacks leader who is serving a four-game suspension for violating the NFL's performance-enhancing substance policy. The challenge couldn't be any more daunting: Indianapolis opens the season Sunday night, on the road, against the defending AFC champion Broncos and record-breaking quarterback Peyton Manning, the former Colts star.
Everyone will be watching to see if Werner and the Colts' defense can hold up against the Broncos' prolific offense.
''The young pass rushers have to step up. It was all Robert, Robert, Robert last year, so we'll try to help him out a little bit, too, when he comes back,'' Werner said. ''It can't just be everything on him. We're trying to get that counterpart with some young guys to step up and get some sacks, too, finally.''
Werner has gotten accustomed to proving himself over the years.
As a foreign exchange student from Germany, he had to show college coaches he could excel at America's most popular sport. After emerging as a pass-rushing menace during his first two seasons at Florida State, he had a 13-sack junior season that netted him the ACC's Defensive Player of the Year award and prompted him to leave school early for the NFL. Colts general manager Ryan Grigson was so impressed that he took Werner with the No. 24 pick in the 2013 draft.
The Colts then moved Werner, a college defensive end, to outside linebacker. He was mentored by Mathis, who thrived after making the same position change in 2012.
Werner's conversion didn't go nearly as smoothly. He missed most of the preseason with a left knee injury, was slowed in October with a foot injury and wound up making only one start as a rookie, finishing with 15 tackles and 2 1/2 sacks.
When league officials announced Mathis had tested positive for a banned substance in the spring, the Colts went to a backup plan - plugging in Werner at rush linebacker and asking everyone else to crank up the pressure on opposing quarterbacks. The crew includes outside linebacker Erik Walden, who missed Thursday's practice with an abdomen injury, backup linebacker Cam Johnson, defensive end Cory Redding and Indy's two newest defensive starters, inside linebacker D'Qwell Jackson and defensive lineman Arthur Jones.
''The entire defense has to step up their game and that's what they'll do,'' coach Chuck Pagano said. ''It'll be easy to make the comparisons because (No.) 98 is not going to be out there. It will be a combination of Bjoern and Walden and Cam Johnson, whoever it is. But the whole is always greater than the sum of its parts, right?''
That wasn't the case last year: Mathis set a single-season franchise record with 19 1/2 sacks. His teammates combined for just 22 1/2.
Plus, Mathis used Manning's return to Indy as a launching pad for one of Indy's signature plays, a strip-sack of Manning in his own end zone that turned into a safety. Indy took advantage of the game-changing play by scoring 23 straight points en route to a 39-33 win over the previously unbeaten Broncos.
This time, Manning won't have to worry about his speedy ex-teammate chasing him down, forcing the Colts to find other ways to pressure Manning.
''We know what he wants to do,'' defensive end Cory Redding said. ''He wants to throw the ball, so we have to get bodies around him and make him feel uncomfortable in the pocket.''
Werner has earned the first shot.
The 6-foot-3, 257-pound Berlin native spent most of his offseason in Indy, trying to fine-tune his game. He looked like a different player at training camp and in limited work in the preseason. He knocked down passes, got into the backfield and made life tough for the quarterbacks.
All he has to do now is play that when it counts Sunday night.
''It's what we've waited for,'' Werner said. ''It's a great opportunity. Can't wait to get out there with my teammates and just play football.''
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