Indianapolis Colts pass rusher Robert Mathis has said that his on-field attitude is 'kill or be killed' when it comes to facing the likes of Peyton Manning.

Following the recent clash between the Colts and Manning's Denver Broncos, the former Indianapolis quarterback described his ex-teammate Mathis as the 'hardest hitter'.

Mathis responded by saying on NFL Network's Around the League Live: "It's no big secret that I'm a QB hater. Peyton a good friend of mine off the field but between the lines, it's kill or be killed.

"I hate to put it like that, but he's a competitor. He's going to light up a scoreboard so my job is to just make him uncomfortable as much as possible."

With 11.5 sacks, Mathis leads the NFL and was named the AFC Defensive Player of the Month for October on Thursday.