Chase challenge: Drivers face a test of patience, while feeling urgency to make NASCAR playoff

For drivers such as Dale Earnhardt Jr., patience is definitely a virtue at this point in the season.

Then again, there's a sense of urgency with the Chase for the Sprint Cup championship just two races away.

Only three drivers are assured of being in the 12-car playoff: five-time Cup champion Jimmie Johnson, Clint Bowyer and Matt Kenseth. But the outlook could be a lot clearer after Sunday night's race at Atlanta Motor Speedway.

Earnhardt is ranked seventh in the points, a solid position to maintain his spot in the playoff. Yet he knows major problems at Atlanta and next weekend's race in Richmond could knock him out.

No one is feeling the heat more than defending Cup champion Brad Keselowski, who ranks 11th and has yet to win a race.