Cousins threw an interception and lost a fumble near his goal line, and the Redskins lost control of their playoff future with a 26-15 loss to the defending NFC champion Carolina Panthers.
Washington (7-6-1) could have clinched a playoff berth by winning its final three games but now needs help. Carolina (6-8) kept its astronomical wild-card hopes alive and dealt a serious blow to the Redskins' chances with two weeks left in the season.
"We didn't get it done," said wide receiver DeSean Jackson, who had seven catches for 111 yards. "Obviously it's frustrating because we knew what we had at stake, we knew what we had on our hands and we can't really talk about playoffs until we handle who we need to handle and play better."
After being picked off by Kurt Coleman in the first half to set up a Carolina field goal, Cousins was sacked by Wes Horton and fumbled on the first snap after halftime as the Panthers took over at the 1-yard line. They scored two plays later to take a 20-9 lead.
Cousins finished 32 of 47 for 316 yards with far too many missed throws in a game with such high stakes. Cousins and coach Jay Gruden were at a loss to explain how the usually high-powered offense sputtered at such a key moment.
"We just never got any kind of rhythm whatsoever throughout the whole game," said Gruden, referencing his team going 2 for 12 on third down. "Part of it was the running game was atrocious, part of it was we had no deep passing game and then the other part: Carolina was very good today."
Reigning league MVP Cam Newton showed no ill effects from a shoulder injury suffered last week, throwing for 300 yards and two touchdowns.
"He took a little bit of a shot early on, but when he came to the sideline and had a chance to take a breath he was ready to roll," Carolina coach Ron Rivera said.
The Panthers took advantage of blunders by the Redskins, who lost their sixth consecutive Monday night home game. It was Washington's most lopsided loss since being routed 38-16 by Pittsburgh in the season opener, also on a Monday night.
"We didn't play well enough to win," Cousins said. "Just didn't make enough plays."
FLAGS FOR 15
Newton was penalized 15 yards for unsportsmanlike conduct in the second quarter for taunting Redskins linebacker Trent Murphy after scrambling for a 1-yard gain. The penalty took the Panthers out of field goal range, moving the ball from the Washington 26 to the 41.
"I've got to be better than that," Newton said. "That just can't happen on my part."
Redskins tight end Jordan Reed took an even costlier penalty late in the third quarter when he was flagged 15 yards and ejected for throwing a punch at Coleman. That penalty contributed to Washington settling for a field goal when trailing by 14.
BLACK AND BLUE REDSKINS
The Redskins lost linebacker Ryan Kerrigan to a left elbow sprain, cornerback Quinton Dunbar to a concussion and special teams contributor Houston Bates to a left knee sprain. They were already without linebackers Will Compton because of a knee injury and Su'a Cravens because of an upper-arm injury.
Panthers K Graham Gano made four field goals but missed from 38 to end his streak at 13 in a row. ... Cousins broke his own single-season franchise record for passing yards after throwing for 4,166 last year. ... Coleman's pick was his 11th interception since the start of 2015, the most by an NFC safety in that time. ... The Redskins are 2-15 on Monday night at FedEx Field, which opened in 1997. ... Despite being cleared from the NFL's concussion protocol, Carolina middle linebacker Luke Kuechly was inactive . ... Newton improved to 21-6 in regular-season games played in December or January. .. Panthers RB Jonathan Stewart had 25 carries for a season-high 132 yards.
Rivera on the Panthers' playoff odds: "Without a doubt it's minuscule, but it can happen."
Panthers: Host the Atlanta Falcons on Saturday.
Redskins: Visit the Chicago Bears on Saturday.
For more NFL coverage: http://www.pro32.ap.org and http://www.twitter.com/AP-NFL .
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