LAKE FOREST, Ill. -- When the Chicago Bears square off against a pass-happy opponent, strong-side linebacker Nick Roach is generally on the field for about 20 snaps.

In the last month, Roach's playing time has increased to approximately 40-45 plays in a given week.

It figures to be another busy afternoon for Roach this Sunday since Denver enters the game as the No. 1 rushing offense in the NFL behind tailback Willis McGahee and quarterback Tim Tebow.

"We always in the linebacker room enjoy the challenge of a good rushing team because they're going to test our rules," Roach said. "Plus, it's always a challenge to face really good players like Willis McGahee who's having an excellent year and has been put in a smart scheme that features the power run game."

Because the Broncos will still use three-receiver sets, there are going to be times Roach comes off the field in favor of the nickel back, but keeping an extra linebacker on the field as often as possible seems to make sense when defending Tebow and the Broncos' read option.

"So basically, out of those 45 plays or so I could play, I probably won't be in for as many pass plays as usual, that's the difference," Roach said. "They don't really bring in extra big bodies to run, they just run in general out of all their formations."

Even with limited snaps, Roach is tied for sixth on the team in tackles (44) and No. 5 in tackles for a loss (4).