Johnny Holton got lost in the Raiders playbook early in the offseason program. The undrafted rookie receiver was focused more on plays and less on playing early on, and it had an impact on practice performance.

The Cincinnati alum recognized the issue right away, and made sure it didn’t make a lasting impact.

“During the spring I wasn’t that comfortable with the playbook and was around new teammates,” Holton said Tuesday. “I really worked during the offseason program and over the break to get the plays and routes down so I could apply them in camp and just worry about playing football. After that, it has been about taking coaching and fixing things every day. If you do that, you can be confident and play fast.”

Holton quickly became a fan favorite in training camp, making flash plays in Napa and, more recently, in preseason games. His effort and skill hasn’t gone unnoticed.

“I told Johnny when we hit training camp, I said, ‘You are the most improved player this whole offseason,’” starting quarterback Derek Carr said. “I have never seen someone jump that much since Seth, since I saw Seth (Roberts) make that jump.

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“I’m very happy for Johnny, he’s a great guy, he has a very quiet, humble spirit about him which is cool. But then he goes out there and runs a 4.2 (40-yard dash) past everybody, you know? So, it’s fun for me to see, but at the same time, I’m rooting for him because I want him to be able to help this football team.”

Holton has a real chance to help the team during the regular season. He’s considered the frontrunner for the No. 5 receiver spot –- it seems extremely likely, though ultimately uncertain, the Raiders will carry a fifth wideout -- following a strong camp and a solid showing in Saturday’s exhibition, when he had three catches for 54 yards and a 23-yard kickoff return.

Holton wants to finish the preseason with another strong outing on Thursday against the Seattle Seahawks.

The same can be said for undrafted rookie K.J. Brent, Holton’s chief competition for a receiver spot. Brent hasn’t been quite as dynamic but plays smooth and has improved throughout camp. He had his best game Saturday, equaling Holton with three receptions for 54 yards.

While Holton had to change minds, Brent made a solid first impression as a route runner and someone who can make plays in the air.

“His route-running ability was really good,” Carr said. “Coming in as an undrafted guy, you never know what the story was. He shows up and runs his first route and I thought, ‘How did that guy go undrafted? At least not get picked up late!’ You see the route running, he’s really good with the ball in the air. …He’s fighting for a spot. I think he’s doing a great job. It’ll be interesting to see how this final game goes.”

At 6-foot-4, Brent is four inches taller and a few years younger than Holton, which might be attractive. Holton, however, is quick and can be electric after the catch.

Performance will be key heading into Thursday’s game, but it’s hard to see the Raiders parting ways with one player if the other makes the roster. A practice squad spot might be a consolation prize that keeps the other player in the mix.

While receiver has been the focus of this story, the Raiders have several undrafted free agents with a real shot at the roster. That includes edge rusher James Cowser and defensive lineman Daruis Latham.

Head coach Jack Del Rio was asked about Holton’s emergence specifically last week, but part of his answer could apply to all undrafted free agents entering the final phase of their months-long tryout.

“It doesn’t matter where you come from, how you got here, you get an opportunity,” Del Rio said. “Certainly here with the Raiders, we welcome competition. We give legitimate opportunities for some of these undrafted guys to come in and make our team if they win a spot, so (it’s) great to see that.”