NAPA — Energy was the word of the day for the Raiders as players checked themselves into training camp ahead of Friday’s opening practice.

The new coaching staff, powered by Jack Del Rio, has the players enthused about getting to work.

“During the offseason, I woke up every day like, ‘Man, I can’t wait to get around those coaches,’ ” punter Marquette King said. “They bring so much more energy. Each coach is a different character and I love it.”

That excitement will be needed as the Raiders aim for their first winning season since 2002.

Second-year cornerback T.J. Carrie said the staff brings the fire first thing in the morning.

“From getting breakfast in the morning, the energy is always there,” Carrie said. “It’s fun when you have an electrifying group of staff who are willing to put it all on the line each and every moment. You feed off that energy. Them yelling and screaming at you at breakfast is something that you definitely get used to.”

Thursday was the reporting day for all players, but rookies, quarterbacks and a handful of other players have been around since Sunday getting extra preparation before camp begins.

“We got away from it for a month, so to get back out with the coaches and go over some of the plays we’re going to run was good for myself and some of the younger guys,” rookie tight end Clive Walford said.

The Raiders will spend the next three-plus weeks in Napa before returning to their Alameda headquarters Aug. 25. Walford said he’s ready to get started and isn’t worried about any wine country heat waves.

“Camp is always a grind so you’ve just got to come with that mindset,” said Walford, a third-round pick out of Miami. “I’m from Florida so this heat ain’t really nothing for me.”

Many eyes will be locked on how Walford and first-round pick Amari Cooper connect with quarterback Derek Carr after their work together was limited by Carr’s finger injury that kept him out of most of the OTAs. Carr and Cooper put in some extra work together after the team’s June mini-camp to build a better connection before camp kicked off.

“I wanted to build a rapport with him,” Cooper said. “It was beneficial because we got a couple of days to throw. He is very accurate with the football.”

Like all teams, there’s optimism at the start of camp. The Raiders feel like they can make strides this season, but King understands there’s not much point in verbalizing why or how the Raiders will be better.

“I’m gonna just let y’all see,” he said. “I don’t even want to talk anymore. I just want to let the team do what they do. We’ll just let the playing talk.”

Follow Jimmy Durkin on Twitter at Twitter.com/Jimmy_Durkin.