CHARLOTTE — Baker Mayfield still had a defiant edge.

His teammates said they still support him.

His coach said it was too soon to think about the big picture or changes at the position.

What's undeniable after four games is that the Panthers' passing game isn't working, and Mayfield, in particular, has struggled to find consistency. He threw a couple of interceptions, continued to have passes batted down at the line of scrimmage (five more, one of which was picked off), and failed to move the offense until the late stages Sunday in a 26-16 loss to the Cardinals.

Asked about his struggles after the game, Mayfield referred to it as: "A four-game stretch."

"It's frustrating; we're frustrated. But it's not the end of the world," he said. "We can still turn this thing around. We're four games into the year."

Perhaps that's the case, as there are still 13 games to play. But Mayfield's season so far has not brought the returns the Panthers were anticipating when they traded for him in July (at the end of discussions that began in the early spring).

Looking at the particular stats from this game might be putting too fine a point on it.

In four games this year, he's completing 54.7 percent of his passes, with four touchdowns and three interceptions, for a passer rating of 74.9.

In four seasons with the Browns, Mayfield completed 61.6 percent of his passes, for 95 touchdowns and 57 interceptions, for a 87.5 passer rating. Even last year, when he struggled through an injury to his non-throwing shoulder, he completed 60.5 percent of his passes with 17 touchdowns and 13 interceptions for a 83.1 rating.

In short, he's never necessarily played like this, pointing to issues that transcend any one player.

Asked if he was being put in the best position to succeed, Mayfield deflected it quickly.

"Yeah, I'm not going to fall for that trap," he said. "We have plays to be made. We've got to find ways to move the ball; we have a good game plan. We just didn't execute it."

Previously this year, Mayfield's come into post-game interviews with a clipped tone, never suggesting anything resembling panic. Sunday, he was visibly more agitated, admitted he wasn't thrilled with the result, but continued to take the long view.

"Obviously, I'm frustrated with the fact we're 1-3," he said. "I mean, we're four weeks into the year. We can sit here and let you guys pile on us, but we're going to come together as a locker room. That's exactly how we're going to handle it. I don't really care about the fact our fans are booing or what's going on. We're going to figure it out. When we win, it'll still be just us in the locker room. We're going to be just fine."

Asked if he was bothered by the fans booing him late in the game, he replied: "Did we go down and score a touchdown after they started booing? Yes."

Those who know him well weren't necessarily surprised by that reaction. Guard Austin Corbett, who was part of Mayfield's 2018 draft class in Cleveland, said it was consistent with how he responds.

"The story of his life has been responding to adversity and responding to people who tell him he can't do something," Corbett said. "So I know he's ready to get back in the building, learn from this, make the changes, and continue on. It's a long season."

Head coach Matt Rhule was upfront about the offense's struggles — there's no denying them, really, not when there was more than a 17-minute difference in time of possession, and they went 2-of-10 on third down conversions. That brought their season percentage down to 25.5 percent, and they entered the game 31st in the league in that category at 27.0.

But Rhule wasn't entertaining questions about the possibility of switching quarterbacks. Sam Darnold is eligible to return from injured reserve as soon as Monday, after missing the first four weeks with an ankle injury.

That those questions are being asked shows how things are going at the moment.

Wide receiver DJ Moore had his most productive game of the season with six catches for 50 yards, but said no one can point fingers.

"Fair to put the loss on him? No, it's a team game," Moore said when asked about Mayfield. "If one person doesn't do their job, it affects the other 11. So it all goes hand in hand. Nobody's looking down on anybody right now."

Running back Christian McCaffrey, who scored the only offensive touchdown in the fourth quarter when it was too late to keep running (he had just eight carries for 27 yards), brushed aside questions about the need for change.

"I'm not a coach," he said. "I know all of us, as well as myself, have full confidence in Baker and his ability to play football."

Mayfield clearly does as well. Asked about his pattern of having passes batted down at the line of scrimmage, he said the answer was to "play the next play."

But he clearly wasn't happy with his play.

"When you turn the ball over that many times, and you lose a game you feel like you should have won, and I feel like we should have won that game, it should piss me off," Mayfield said. "You should never be happy with losing, and I never will be.

"I expect more out of this group. I export more out of myself. But we're going to stick together. That's really all I care about. We're going to keep going; we're going to figure it out."