Cousins was 30-of-49 for 316 yards in a 32-21 loss to the New York Giants, but he had two interceptions, including one deep in Washington territory by Prince Amukamara that set up a first-quarter touchdown. Cousins now has nine interceptions in three games against the Giants.
Despite the struggles, Gruden said he never considered playing backup Colt McCoy.
"No. No. Kirk was fine," Gruden said. "... We've got to play better around him. There is no quarterback controversy whatsoever."
"When you're throwing the ball across the middle of the field like that, you better be dang sure that it's complete or throw it away [so] you live to fight another day on second-and-10," Gruden said after the game. "So that was unfortunate."
"We got to do some things around him. We can't make this all about the quarterback," Gruden said. "We got to create some turnovers on defense. We got to continue to run the ball, and the receivers got to make some plays. And Kirk's got to do better. We've all got to do better."
Robert Griffin III, who lost the starting job to Cousins during the preseason, was listed as the third-stringer and was a healthy scratch for Thursday's game.
The Redskins host the Philadelphia Eagles in Week 4.
ESPN Staff Writer John Keim contributed to this report.