ARLINGTON, Texas -- The plan for the playoff-bound Washington Redskins going into Sunday was not without its potential issues.

"You play to win the game and you also don't want to lose anybody," Redskins coach Jay Gruden said. "There is a fine line in that. I felt like whatever decision I made could have been horribly wrong."

No need to worry.

Quarterback Kirk Cousins passed for three touchdowns and the NFC East champions closed out the regular season by rolling past the Dallas Cowboys 34-23 Sunday afternoon at AT&T Stadium.

Washington (9-7) heads into the playoffs on a four-game winning streak, the team's longest since 2012. The Redskins will host a wild-card playoff game next Sunday against the Green Bay Packers (10-6) with momentum on their side.

"It's worth something," Gruden said. "I'd rather do that than lose a couple of big games. Regardless of your winning streak or losing streak, come Saturday or Sunday next week, we're going to have to come together and play a great football game against a quality team."

The Cowboys (4-12) had a merciful end to one of the worst seasons in franchise history. Injuries to quarterback Tony Romo and receiver Dez Bryant began a downward spiral one year after winning the East.

"Clearly, we didn't get the job done, for a lot of different reasons," Cowboys coach Jason Garrett said. "We didn't handle the adversity of the season very well."

That title of East champ now belongs to the Redskins, who finished last in the division in six of the previous seven years.

Cousins did his damage early, connecting with receivers Pierre Garcon, Jamison Crowder and Ryan Grant on touchdowns as Washington raced out to a 21-0 lead in the first quarter.

There's no question the Redskins wanted to win the game.

"It was important -- 9-7 sounds a lot better than 8-8," Cousins said. "In addition to that, we felt like it was important to go into the playoffs with momentum and rhythm.

"We obviously felt good about the last three weeks winning three straight. We didn't want to go into the playoffs having broken that streak, so to put together now four straight in the fourth quarter of the season is important."

Cousins (12-15 for 176 yards) was replaced by backup quarterback Colt McCoy in after one series in the second quarter. McCoy had a 71-yard touchdown to wide-open receiver Rashad Ross in the fourth quarter.

Running back Alfred Morris had 100 yards rushing on 19 carries. Morris last hit the century mark in the season opener against Miami.

Cousins set the franchise record for passing yards in a season (4,166) before departing with a 24-0 lead. He had been one of four quarterbacks to take every offensive snap for his team this season.

Gruden was able to substitute liberally, making sure banged up starters such as tight end Jordan Reed, receiver DeSean Jackson, running back Matt Jones and tackle Morgan Moses took it easy.

Dallas quarterback Kellen Moore showed flashes in his second consecutive start, but it wasn't all pretty. Moore is hoping to be an option as Romo's backup next season.

"Bottom line is that I am really appreciative of this opportunity," Moore said. "A lot of guys wait in my situation and never get the chance to play in an NFL game."

Moore completed 33 of 48 passes for 435 yards, with three touchdowns and two interceptions. Moore hooked up with receiver Cole Beasley twice and tight end Jason Witten for the three touchdowns.

Moore had two turnovers in the first quarter, an interception and fumbled snap, leading to Washington touchdowns that put Dallas in a huge hole.

One of the few positives for Dallas this season was running back Darren McFadden. Despite his ups and downs, McFadden still managed to rush for 92 yards and finished the 2015 season with 1,089 yards.

McFadden did have a fumble while going in for a sure touchdown in the fourth quarter. The ball rolled out of the end zone resulting in a touchback for Washington.

Since the advent of the 16-game schedule, the only worse seasons for the Cowboys were 3-13 in 1988 and 1-15 in 1989.

NOTES: Cowboys LB Sean Lee was inactive with a hamstring injury, costing him a $2 million escalator in his contract. Under the terms of his deal, Lee had to play in 80 percent of the defensive snaps this season to trigger the bonus to his $3 million base salary. Lee had played in 82 percent going into the regular-season finale. It was his decision not to play. ... Other Dallas inactives were CB Morris Claiborne, G La'el Collins, QB Jameill Showers, WR Rodney Smith and WR Vince Mayle. ... Redskins inactives: LT Trent Williams, QB Robert Griffin III, DE Jason Hatcher, RB Matt Jones, S Dashon Goldson, CB Quinton Dunbar and LB Perry Riley, Jr.