As they made their way through the second and third quarters of the season, keeping pace with the NFC’s playoff contenders, the Washington Redskins could regularly count on quarterback Kirk Cousins. With ambitious throws, keen instincts, and great anticipation, Cousins carried his offense, compensated for shortcomings on the defense, and led the Redskins to key victories.

Even in some of the losses — two in the past three weeks — Cousins played well enough to keep his team in games and give them a chance to win.

But Monday night, with his team in need of some of those clutch plays, Cousins didn’t have his stuff. The offense couldn’t get into a rhythm, and the Redskins fell, 26-15.

Cousins threw for 315 yards, completing 32 of 47 passes. But as a whole, Monday night’s game was one of his worst outings of the season. He threw an interception and fumbled once on a sack; the Panthers turned those takeaways into 10 points. And Cousins posted a passer rating of 77.9 — his second lowest since the 72.7 rating in the season opening blowout loss to Pittsburgh. (He’d posted passer ratings of 110.9 or better in four of his past five games).

Cousins and the offense converted only 2 of 12 third downs. The Redskins went three and out five times in the game — alarming considering that entering the game, they had 15 three and outs all season. The Redskins ventured inside the 20-yard line three times but managed just one touchdown.

(Elyse Samuels/The Washington Post)

The 15 points mustered by the Redskins — a rushing touchdown and three field goals — marked a season low for the NFL’s second-ranked offense.

“I thought they did a really good job,” Cousins said of the Panthers. “I thought defensively they executed really well. Their defensive backs played very well, reacted to routes really well and their linebackers played well. . . . It’s a good defense.”

The Redskins knew that they would have a hard time running the ball against the Panthers. Carolina entered the game with the third-best run defense in the NFL. However, Redskins players and coaches expected to have opportunities for success in the passing game. Carolina’s defense ranked third-worst against the pass.

But Cousins wasn’t sharp from the start, missing his mark to open receivers on first and third down of the first Washington possession, and the Redskins went three and out.

On the next series, Cousins appeared tentative and settled for short passes instead of trying to go deep to primary receivers. The Redskins managed to work their way downfield, but the drive stalled at the Carolina 25-yard line. Cousins tried to force a longer fade pass to Pierre Garcon down the left sideline. But he missed tight end Jordan Reed running free into the end zone, and slot receiver Jamison Crowder streaking across the field uncovered.

Cousins missed locating open receivers on two other trips inside the red zone as well.

“I thought he had pretty good time to throw it,” Coach Jay Gruden said. “They mixed up their coverage and he had problems seeing the coverage. I don’t know if he just didn’t have clear throws or what. We’ll just have to wait and see [the video].”

Asked about the lack of shots downfield — particularly after Cousins and DeSean Jackson had connected on throws of 60 yards or longer in each of the past three games — Gruden explained, “Their safeties were playing pretty high on occasion and we had a few downfield shots, but they had them too deep and we couldn’t really get it down there.”

The blame couldn’t fall entirely on Cousins, however.

Several receivers dropped passes they normally would have caught. Tight end Vernon Davis let a would-be touchdown catch fall through his hands. Garcon — who hasn’t had a drop all season — bobbled and dropped a three-yard pass on a crucial third and two, and Jackson had two third-down throws go through his hands as well.

First-half struggles spilled over into the second half, when on the first play of the third quarter, Cousins was sacked and stripped of the ball, and the Panthers recovered at the Washington 1-yard line. The Redskins only came within striking distance once the rest of the third quarter, but had to settle for a field goal after a penalty on Jordan Reed for throwing a punch backed the team up to the 27-yard line.

Further complicating matters: the Redskins couldn’t get anything going in the rushing department.

Running back Rob Kelley managed only eight yards on nine carries. His longest run was a five-yard touchdown dash up the middle in the second quarter. But otherwise, rushing yards were hard to come by, and Washington finished the game with 29 yards on 13 carries. The longest run was a 12-yard Cousins scramble on a broken play.

Without the aid of the ground game, Washington’s offense became one-dimensional, and continued to sputter.

“We were outcoached today, there’s no question about that,” Gruden said. “And, they played better than us, I think.”

Cousins echoed the coach’s sentiments when asked if he felt off throughout the night, or if he could pinpoint anything in particular that the Panthers did to disrupt the offense.

“I think they just played better than we did,” the quarterback said.