Nick Folk tied it at 13 with a 39-yard field goal early in the second half. Two plays later, the Jets got the ball back when Darrelle Revis made an easy interception of Cousins' pass for Ryan Grant.
"If I start to doubt, I'm not going to ever get to the level I want to go," Cousins said. "I've got to keep going, learn from mistakes."
Gruden dispelled any murmurs of a quarterback controversy, saying the Redskins are sticking with Cousins.
The Jets, coming off a bye-week break, trailed 13-10 at halftime, with the Redskins (2-4) scoring their points off three turnovers by Bashaud Breeland,
Cheap Air Jordan Shoes Wholesale, including an interception and two fumble recoveries.
"He's deceivingly fast," a smiling Decker said of Fitzpatrick. "He's an athlete."
But New York opened the second half with 24 straight points to take control against a Washington team without several injured starters, including wide receiver DeSean Jackson, left tackle Trent Williams and cornerbacks DeAngelo Hall and Chris Culliver.
With so many injuries, even Robert Griffin III was active