CINCINNATI — The Panthers don't know who will start at quarterback when they play four days from now against the Falcons.

More importantly, they don't know why they played the way they did Sunday against the Bengals.

Interim coach Steve Wilks said he didn't have an answer about the next game, after he pulled starter PJ Walker after a calamitous first half in the 42-21 loss at Paycor Stadium.

"I couldn't tell you right now," Wilks said. "We'll be able to sit here and look at a few things and talk to the staff, and I'll have that answer here soon.

"I'm not going to get into hypotheticals. Right now, coming off this game, we need to watch the tape and figure out where we are in all three phases. And get guys to step up as well as coaches and myself."

As they look at this one more closely, they're not going to see a lot they like.

Walker was the bad version of himself Sunday, completing 3-of-10 passes for 9 yards, with two interceptions in the first half for a 0.0 passer rating. After he played two straight competent games (the win over the Buccaneers and last week's overtime loss to the Falcons), it was a jarring performance, going back to some of the uneven play of his first two seasons with the Panthers (when he had two touchdowns and eight interceptions).

And that made it hard to explain why it went that way.

"I'm not really sure," Walker said. "Prepared my ass off this week. Things just didn't go my way. Overall as a team, we didn't play our best football, and that started off with me."

That general malaise was evident, as his turnovers and lack of rhythm were compounded by a defense that couldn't stop Bengals running back Joe Mixon, and penalty problems that went through the entire roster (seven for 50 yards, a weird mix of special teams mistakes and false starts and defensive neutral zone infractions). But Walker also acknowledged some "bone-headed mistakes," and the early hole that set the stage for the entire day. The only first down of the first half came on a Bengals penalty, and the Panthers were 0-of-4 on third downs, and ran for just 23 yards after that had been the staple of the last two games.

"It was flat out there today. It was flat all around. All three phases," Walker said. "We've just got to continue to get better. Don't let this one game define us. This ain't us. This ain't us."

There had been signs that the Panthers were showing life, that they were playing the kind of football under Wilks that would provide some degree of hope. They went into Atlanta a week ago with first place in the division within reach, but Sunday, answers seemed to be just beyond their grasp as well, if not farther away, as they sit 2-7 with eight games to play.

"It didn't feel like us on that football field," Walker acknowledged. "Didn't feel like us. On the sideline, there was no energy. That's on this team; we've got to get that right and continue to get better, and continue to play for one another. Eliminate the me and go out there and build a we team."

Walker said Wilks was very matter-of-fact about the benching, the same way he was when he told the group Walker would start.

"Just continued to be honest with us, and we were going to go with Baker in the second half," Walker said.

And while Baker Mayfield had a better second half, he wasn't celebrating the fact he led three scoring drives, throwing touchdown passes to Tommy Tremble and Terrace Marshall Jr. Mayfield finished the game 14-of-20 for 155 yards and the two touchdowns, with a 126.0 passer rating that was the highest of his Panthers career (well beyond the 84.6 rating he posted against the Browns in the opener).

But he also acknowledged that by the time he got in the game, the Bengals were playing "precautionary defense" and that there were a lot of check downs he simply accepted.

Neither of the quarterbacks had any indication of what the next step was.

"I'm going to continue to go out there and work," Walker said. "Continue to put the time in, and put the work in, and let coach Wilks make that decision. That ain't on me, that ain't on Baker, that's on coach."

"I want to win," Mayfield said. "Whatever my role is and however I can help, that's what I want to do.

"Not getting into that. Not my decision. I want to win. Whatever role gets decided, I'm going to do it, and I'm going to do it extremely well."

He also agreed with Walker's assessment of the mood because there was no disputing that they weren't playing at the same pitch as the last two weeks.

"It was more so everybody talking. You've got a decision to make team-wide," Mayfield said. "You can keep fighting and come out of this thing proud of what you put on tape, or you don't. This is a team, obviously, things didn't go our way today, and that falls on everybody. That was a full-blown team loss.

"I agree with him (Walker). I don't know if I can give you an explanation as to why. That was the message at halftime as well. We talked about there's a decision to make. You either get up and you fight because that first half was bad football, all the way around, all three phases. It just wasn't good. A lot of penalties. It just wasn't good. It was flat; it just wasn't us."

Now, as the Panthers prepared for a quick flight home and a quick turnaround before Thursday's game, they have a number of things to consider.

Quarterback Sam Darnold can be activated this week, and has to be by Wednesday to be eligible to play again this season. But it seems unlikely he'd be a factor in starting against the Falcons since he hasn't taken a game rep since the preseason. So that leaves deciding between Walker and Mayfield, and hoping the entire team plays something closer to the complementary football they had played when the run game and the defense were doing their part to make Walker's life easier.

Now, Wilks has a decision to make, and in the moments after that game, he didn't indicate any lean.

"We started slow and couldn't stop the bleeding. I put all that on me," Wilks said dutifully to begin his press conference.

"Did I expect us to play the way we did?" he said later. "Not in a million years."