Robert Mathis continues to defy expectations long after joining the Indianapolis Colts as a relatively obscure fifth-round pick out of Alabama A&M in 2003.

Mathis is in his 11th season and, like his old teammate Peyton Manning, is playing better than ever. Mathis leads the NFL in sacks with 9.5 sacks, the second-most in the first five games in NFL history, behind only Carolina's Kevin Greene's 10 in 1998.

Mathis will be chasing San Diego Chargers quarterback Philip Rivers on Monday Night Football this week.

Here's a quick look at Mathis:

Ht: 6-2; Wt: 246; Age: 32; College: Alabama A&M; How acquired by Colts: Drafted 138th in the fifth round of the 2003 NFL Draft.

Fast facts: Mathis has 101 career sacks, trailing only former teammate Dwight Freeney (107.5) in the Colts' record books. ...He has four career 10-plus sack seasons and has been in five consecutive Pro Bowls. ...He ranks third behind Jared Allen and DeMarcus Ware in total sacks over the last 10 seasons and ranks 27th in career sacks in NFL history.

Mathis on leading the NFL in sacks: "Still doing what I've been doing over the last 10 years. Sometimes the balls roll to your favor. I'm feeling highly blessed right now."

Mathis on watching his peers: "Sack guys, pass rushers, we keep up with one another. I see what they're doing. I study film of them and whatever they're doing that can help me out, I'll do it. Whatever I'm doing that can help them, they'll do it."

Mathis on former teammate and Chargers defensive end Dwight Freeney being injured: "As a friend, I'm extremely bummed. As a competitor, not that bummed because he won't get a chance to hit my quarterback. But we talk all the time and he knows that it's not going to be the same without him."

Mathis on why the Colts have traditionally struggled against the Chargers: "They come in and they're pros, they're a good team. You can't take anything away from them, you just have to be on top of details. In the past, they've made you pay when you're not on top of it."

Chargers quarterback Philip Rivers on Mathis: "Anytime you have over 100 sacks, you're really, really, really good at what you do. Obviously, most of those years it was he and Freeney both. The combination of those two guys had been an unbelievable duo for a long time. Mathis, the thing about him is, he not only gets sacks...he wants the ball. He's got such a knack for sack/fumbles."

Mathis on playing MNF: "It's the only show in town, Monday night. Everybody has heard about you, now they're starting to see what you've got and you just have to put it on the field."