LANDOVER, Md. – Baker Mayfield and Sam Darnold are taking the Panthers' quarterback competition seriously.

Carolina's 23-21 preseason win over the Commanders on Saturday added some tape against another team to the evaluation process between Mayfield, the Panthers' newest addition to the quarterback room, and Darnold, last year's starter.

Mayfield, stoic after earning the first start of the preseason, said he saw "some good, some bad" out of himself during his first game with the Panthers. Darnold, after tossing the team's lone touchdown pass, said he's focused on doing all he can with every play he's given.

Head coach Matt Rhule appeared impressed by each.

"(With) both guys, I have to really watch the tape to see exactly what they did," Rhule said. "But I thought they were both in command. We made the right checks, so (I) was pleased."

Mayfield got the start and said it was simply his "turn" to guide the first-team offense against Washington, but the competitive mentality wasn't altered by getting snaps with the first team against the Commanders.

Rhule said Mayfield's starter designation was for Saturday only, and that film from the Washington matchup would help inform later decisions about a starter down the road.

Mayfield, who signed with the Panthers roughly a month before the first preseason game, also said he's significantly more comfortable in offensive coordinator Ben McAdoo's system after going through training camp.

"(It's) night-and-day different, that's for sure," Mayfield said. "(It's) a lot more comfortable now, and I think that kind of permeates throughout our whole offense. Obviously, Sam's got great command of the offense as well, so we just have to be the leaders and continue to try and improve."

Mayfield's efforts led to a game-opening field goal on the opening drive. He took 12 snaps, led the offense 54 yards downfield and went 4-of-7 for 46 yards passing, which helped set up Zane Gonzalez for a 41-yard field goal attempt and the first points of the game.

"We had an opportunity to go down there and score a touchdown," Mayfield said. "Getting a field goal, points are always good on the opening drive, but it's just the frustration of not ending up in the end zone."

Mayfield connected with receiver Shi Smith twice on third down – first for 19 yards and then for a gain of 15. The Panthers went 3-of-4 on third down with Mayfield under center.

He also flashed his ability to throw downfield, attempting a deep pass to Robbie Anderson from the Commanders' 39-yard line. The throw hit Anderson's hands, but was broken up by Washington safety Bobby McCain near the goal line.

But Mayfield later fumbled a snap and recovered that mistake before the drive ended with an incomplete pass on third down.

"Proud of the group converting a few third downs, driving the ball down the field," Mayfield said. "Obviously (I've) got to clean up the center-QB exchange. That's 100 percent my fault."

Mayfield's day was done after his first series, which fulfilled Rhule's plan for both him and Darnold to get at least 8-10 snaps under their belts against the Commanders.

"Still a lot to build on," Rhule said. "But I did think he moved the ball, looked in control (of) a nice long drive to start the game. It looked somewhat clean until the very end."

Darnold entered the game with the benefit of excellent field position, after Jeremy Chinn forced an Antonio Gibson fumble, recovered by Amare Barno at Washington's 19-yard line.

The Panthers scored after three plays, thanks to Darnold's 11-yard pass to Brandon Zylstra and an impressive 8-yard touchdown throw to Rashard Higgins.

"(Darnold) made a courageous play," Rhule said. "The hat was on his head. He stepped up and made it."

Darnold came back out for another series, taking another three snaps with a different result. He went three-and-out on his second set of downs, with his lone pass attempt of the drive spiraling to the ground.

He finished 2-of-3 passing for 16 yards and a touchdown.

"To be able to actually get in there and to get hit a couple times too – obviously, it's not ideal – but it's good to kind of shake those cobwebs off, because you obviously don't get hit during practice," Darnold said. "It was good to get back out there, get hit a couple times and kind of feel that pressure of a real game."

Despite the Mayfield versus Darnold battle, it was the next man up behind them – PJ Walker – who actually took the bulk of snaps under center.

Walker, listed as the second-string quarterback behind an "or" designation for Mayfield and Darnold on the Panthers' first depth chart, came out before rookie Matt Corral.

Walker entered just before halftime and stayed in throughout the third quarter, finishing 10-of-19 for 136 yards.

"Just move the ball – that was my goal – to come out here, and move the ball up and down the field as much as possible," Walker said. "I felt like we did a pretty good job today."

Walker didn't throw for a touchdown, but he did lead two scoring drives that resulted in 10 points thanks to a Spencer Brown short touchdown run and another Gonzalez field goal.

"PJ's had very, very limited reps, and he's had a really good camp," Rhule said. "I think Ben's been highly, highly, highly impressed with some of the things that he's done."

Corral took over in the fourth quarter, completing his first attempt to Keith Kirkwood for 11 yards before finishing the day 1-of-9 overall. A couple of Commanders penalties played a role in extending Corral's game-winning field goal drive to secure the Panthers' win.

In the battle for a starting job, Rhule said he's keeping options open as he reviews the tape from Saturday and prepares for the upcoming week with the Patriots. Carolina will hold joint practices with New England before preseason game number two next Friday at Gillette Stadium.

"Sam got us in the end zone, Baker led us down the field," Rhule said. "So it looked like both guys played well in terms of production. We'll go back, and look and see where they are."