The Washington Commanders' Week 1 loss to the Tampa Bay Buccaneers beget a fair number of questions about the roster, and most of them were directed at the defense. Baker Mayfield had a day in the season opener, completing 80% of his passes for 289 yards and four touchdowns. Washington's new coaching staff preached a "run and hit" system, but there wasn't much of either in the 37-20 loss.

Flash forward to November, and there are fewer concerns about the unit heading into the final third of the season. Communication is sharper, the calls are better and yes, there's plenty of running and hitting from the players. A bottom five defense has since climbed closer to the league average, even performing better than most in areas like passing yards allowed (5th) and sacks (T-12th).

Those improvements have kept Washington competitive against top-tier teams like the Pittsburgh Steelers and Philadelphia Eagles. The only problem is that they start to tail off in the fourth quarter, and that's when the questions pop up again. It's been an unfortunate trend for the Commanders, as opponents have either closed the gap or snatched leads from them in the final minutes of regulation.

Defensive coordinator Joe Whitt Jr. and his players know that's something they need to fix.

"We played...well for 53 minutes," Whitt said of the Commanders' 26-18 loss to the Eagles. "But it's a 60-minute game. We talk about finishing and winning moments, and we didn't get that done."

The factors that led to Washington dropping games against the Steelers and Eagles are different, but they do have similarities in terms of the defense's performances. For three-and-a-half quarters, the unit held both offenses largely in check. Steelers quarterback Russell Wilson barely had 100 yards heading into the fourth quarter, and the Eagles, who averaged 29.4 points per game in their previous five matchups, had just 12 points with eight minutes left in the fourth quarter.

That's where the regression started for the Commanders in both games. The Steelers gained 144 yards -- 46% of their total for the night -- on 25 fourth-quarter plays and converted four third downs. The Eagles scored touchdowns on three consecutive drives in the fourth quarter, fueled by Saquon Barkley's 84 yards.

Those kinds of lapses, particularly after playing well for most of the night, are justifiably frustrating for the defense.

"It's just a whole other level of focus," defensive tackle Daron Payne said Wednesday. "Towards the end, you just gotta dial in even more."

It's not as if Whitt is making different calls in the fourth quarter. The concepts are the same ones that held the Eagles to six points for most of the evening last Thursday and limited the Steelers to three third-down conversions. The problem is that elite players like Saquon Barkley and even schemes like the one in Pittsburgh need complete focus and execution on every play. Benjamin St-Juste knew that Wilson likes to throw fade routes that close to end zone but didn't play the 32-yard touchdown pass to Mike Williams in the correct way. Percy Butler missed a tackle on Barkley, which would have forced a fourth down but instead turned in a 43-yard gain.

It's also not as if the players are playing hard; they are, but execution matters against the top teams.

"We were in the calls that we wanted to be in," Whitt said. "So, that's where I'm disappointed. Because we hit it early, but it's 60 minutes."

For head coach Dan Quinn, it creates a challenge of having to balance praising the good plays from the first 50 minutes while not minimizing the negative plays. One thing he does love, though, is the first-hand experience of learning why it's important to execute for an entire game.

"Being battle tested is really important, and it doesn't happen during the easy moments," Quinn said. "It happens during the hard moments, and those are the ones that you do have to go through. It sucks when you're going through them, but you do have to go and know...this is the finishing time, this is the finishing moment offensively, defensively, [special] teams, whatever that looks like."

After failing against two of the league's best teams in games they could have won, it sounds like the players have learned the lesson. Safety Quan Martin said in the locker room that he and his teammates want to put an emphasis on finishing in this week's slate of practices.

"I think that's been a weak part of our defense these last couple of weeks of being able to finish the game in the fourth quarter when it's in our hands," Martin added.

The Dallas Cowboys, who will come to Northwest Stadium with a 3-7 record, are the first opportunity for the defense to show they can finish games. While the Cowboys still have talent on offense, they are suffering from injuries on the offensive line and at quarterback with Cooper Rush replacing Dak Prescott, who is on season-ending Injured Reserve. The offense has sputtered with Rush under center, producing 146 yards against the Eagles and just 10 points against the Houston Texans.

Whitt, who coaches for the Cowboys from 2021-23, still isn't overlooking his former team.

"I know how hard those players in that locker room work and how they prepare and how they get ready," Whitt said. "So, this is going to be a very, very hard game."