That's because as the Giants face teams that have different offensive tendencies, his playing time changes. Two weeks ago against the run-happy Ravens, he played 41 snaps on defense. Last week against the air-it-out Cardinals, he was on the field for only 13 plays, as nickel and dime packages relegated him to the sideline.

"Up, down, up, down," he said. "That's how it is when you're playing these different offenses, but that's part of it."

Blackburn and Danny Clark expect to be on the field a lot more Sunday against the Redskins. They have the NFL's top running back, Clinton Portis, as their primary weapon.

"I believe the Redskins ran the ball 30-something times last week, so Danny Clark and Chase and the other linebackers will be happy about that because they are on the field," linebacker Antonio Pierce said.

After the Redskins, the Giants face the Eagles. When they squared off Nov. 9, Blackburn was on for only 14 snaps against Philadelphia.

"You have to have every package ready, adjust to what the offense is doing," he said. "It's a chess match."

And Blackburn is the starting pawn.

No clinching

Because the Cowboys beat the Seahawks yesterday, the Giants can't clinch the NFC East title with a win over the Redskins on Sunday. But if the Giants win on Sunday, they'd be able to secure their first division crown since 2005 at home when they face the Eagles on Dec. 7.