A quirk in Rush’s contract could impact which quarterback gets the primary share of snaps in Dallas’ season finale vs. Washington.

Rush, who also is scheduled to become a free agent in the offseason, has started every game since Dak Prescott’s season-ending hamstring injury. The Cowboys are 4-4 in Rush’s eight starts. He has earned a $250,000 incentive by playing 45 percent of the snaps this season. If he reaches 55 percent, he earns another $250,000.