ENGLEWOOD, Colo. -- Champ Bailey admits he knew nothing about linebacker Mario Haggan when he arrived in Denver midway through the 2008 season, following a five-year stint in Buffalo and a resume that included zero starts, a single sack and one suspension.
Bailey quickly saw how versatile and valuable Haggan was.
"He can do it all," Bailey marveled.
It seems like the Broncos are asking him to do just that nowadays.
In addition to his usual special teams responsibilities, Haggan will pull double duty on defense this week with Robert Ayers returning from a fractured foot. He'll rotate between inside and outside linebacker Monday night when the Broncos (3-6) visit the San Diego Chargers (4-5).
The Broncos went away from their 3-4 scheme with three down linemen and four linebackers when Ayers got hurt in early October, two months after NFL sacks champ Elvis Dumervil was lost for the season with a torn chest muscle. They had mixed results, however, with the 4-3 look and ditched it after the bye week.
At outside linebacker in the 3-4 last week, Haggan had his best game as a pro, sacking Kansas City Chiefs quarterback Matt Cassel three times in the first half and forcing a fumble that was returned 75 yards for a touchdown.
"He hit the quarterback another four times right as he was getting the ball off," defensive coordinator Don Martindale noted. "It's something that he's worked on, and Mario has played everywhere we've asked him to play, and the thing that impresses me the most about him is just how unselfish he is. Whatever is called upon, whatever his job is, he just goes out and does it."
His trio of sacks in 30 minutes matched his total from his previous 97 NFL games.
"It's opportunity," Bailey said. "I don't think he had the opportunities in Buffalo that he has here. We're using him everywhere. He does so much for us. If we lost him, it would be a different story on this defense. He does so many things people don't know about."
Haggan played in eight games as a sub for Mike Shanahan in 2008 after returning from a four-game NFL suspension for violating the league's policy on performance-enhancing drugs.
When Josh McDaniels arrived from New England that next offseason, he was, like Bailey, a little unsure what to make of Haggan.
"He hadn't been a full-time defensive player much," McDaniels said Thursday. "I was familiar with the name certainly from playing against them a little bit, but never enough to really have a great feel for him."
McDaniels quickly fell for the all-purpose linebacker, who has started all 25 games for him since.
"I think this defense is really a perfect fit for Mario because it's a downhill, hit-them-in-the-face physical style of defense," McDaniels said.
The Broncos plan to limit Ayers' snaps Monday night as they ease him back, so Haggan will get to do in the game what he does at practice every week: move around.
"It's not easy and it's a credit to him because we've made him learn that basically all year," McDaniels said. "And sometimes that goes unnoticed because nothing goes on during the game to kick him out there but when you're spending hours each week learning a position that you may never play, he's very unselfish."
After spending his first half-dozen seasons playing mostly special teams and filling in on defense occasionally, Haggan is happy to line up wherever he's needed.
"Wherever I am, I will go out and cause havoc," he insisted. "I've been doing it every week this year. I've been preparing at both positions. I'm just happy that they trust me enough to allow me to learn both positions each week and let me display my talents on the field," Haggan said. "I'm happy either way it goes."
So are his teammates, who were thrilled with his breakout game last week.
"We're just happy that he's getting his due because he's been doing some grunt work -- grunt work -- a lot of things that goes unnoticed as far as the things he's been asked to do," safety Brian Dawkins said. "But it's always a good thing when you have a guy that's unselfish like that be able to come up with a big game like that."
Copyright 2010 by The Associated Press