LAS VEGAS -- Just seven games into the season, we've already reached what feels like a critical point for first-year Philadelphia Eagles coach Nick Sirianni and his staff.

The loss to the Las Vegas Raiders Sunday was much more one-sided than the 33-22 final score indicated. It marked the Eagles' fifth loss in six tries and elicited some player reaction that, when viewed collectively, looks like a giant, blinking warning sign.

Team captain Fletcher Cox had a difficult time hiding his dissatisfaction with defensive coordinator Jonathan Gannon's approach. That was true after the game and at one point during it, when the defensive tackle grew animated and yelled toward the sideline following a long third-down completion by the Raiders in the first quarter.

"I wasn't mad at Nick, I wasn't mad at anybody," Cox said. "It was just one of those deals where as a player I didn't kind of agree with what was called on defense so I just kind of let my frustration go, and it's part of the game."

The Eagles were passive defensively Sunday, as they have been for much of the season. With the safeties playing deep and the pass rush unable to generate consistent pressure, Raiders quarterback Derek Carr completed 91.2% of his throws, the second-highest rate in a game in NFL history (minimum 30 attempts), per ESPN Stats & Information.

Cox, as he did a couple of weeks back, again seemed to take issue with the way he is being utilized by Gannon. The 10-year veteran has made a very good living crashing into the backfield and wreaking havoc, but he's now being asked to ride out double-teams and read and react more often in this scheme.

"Honestly, it's not what I'm ... it's not what it's been. Obviously, you just have to play what is being called," Cox said. "When you're so used to playing so aggressive the last however many years I've been playing, it just changed, so you can't be as aggressive.

"You're frustrated and you get tired of 6,700 pounds just laying on you and you want to do something about it. Obviously being the player that I am, you can only take so much and I'm going to do something about it, I'm going to be aggressive."

Sirianni acknowledged the defense needs to "challenge more," saying it "always starts with us as coaches, being able to put them in positions to make plays."

The Eagles had extra time to prepare coming off a Thursday night game and said they used that time to self-scout and make alterations on both sides of the ball. The offensive approach was different, with Philadelphia leaning on the ground game and quarterback Jalen Hurts lining up under center more often, but the results -- seven points through the first three quarters and 15 more when the game was out of hand -- remained lackluster.

The loss was troubling enough that it compelled safety Rodney McLeod to address the team afterward. He was "really challenging guys and asking guys, 'Are you committed to making this run? And if you are, come Wednesday ready to work.'"

"Time is running out," McLeod added. "We have to make a stand and we have to make a push."

Hurts, who finished 18-of-34 for 236 yards with two touchdowns and an additional 61 yards rushing, insisted this team is not at a crossroads.

"I've said it -- I'm really tired of saying it -- but I believe," Hurts said. "You've got to be patient with it, continue to work, keep your faith, keep grinding, head down, go to work. It will turn over."

Cox added that Eagles management "brought this coaching staff here for a reason" and that "it's everybody's first year, so we're all learning."

But some of the frustration that has been bubbling up behind the scenes surfaced Sunday, and there is plenty more where that came from. And it's not just Cox. The not-so-subtle jabs at the coaching scheme, the challenge by McLeod referencing his teammates' level of commitment -- these are actions more commonly associated with sinking-ship seasons late in a coach's tenure. It's odd to see them appear seven games into a coach's first season, which is typically still considered the honeymoon period.

Cracks can spider out pretty quickly in the highly pressurized NFL. Sirianni and his staff have to find a way to seal them before things go from bad to worse.