David Johnson wore a mischievous smile following training camp practice on Sunday afternoon, like he knows something everyone else doesn't.

The Cardinals running back was a breakout star in 2016 -- nearly becoming the third player in NFL history to amass 1,000 rushing and receiving yards in the same season – but has been unable to reach that height the past two years.

There are legitimate excuses for each season – a wrist injury in 2017 and poor utilization in 2018 – and there is great belief coach Kliff Kingsbury will unlock Johnson's talents in 2019.

Johnson is such a versatile piece that the imagination runs wild when considering his usage – from zone read handoffs to screens to vertical routes from the slot -- but as his demeanor suggested, all that will remain under wraps until the regular season begins.

"I like the way Kliff is doing it," Johnson said. "He's not letting anyone know, including (the media). And I'm going to keep it that way as well.

"We're not going to show our cards right away."

While the specifics are unknown, Johnson figures to be one of the biggest beneficiaries of Kingsbury's hire. Texas Tech playmakers routinely received the ball in advantageous spots, and as the most talented player on offense, Johnson should garner the same treatment.

Last year, he said, it felt like he was "getting hit by five, four, nine guys" at a time. This season, "there's going to be more space for me to create and be effective."

By spreading defenses out, there will be fewer players in the box when he gets handoffs, and the threat of mobile quarterback Kyler Murray pulling the ball at the mesh point will keep the run-stuffers from zeroing in on Johnson.

"In previous years, D-ends just slammed down right at me," Johnson said. "Now they've really got to try to read it. Kyler's a fast guy, too. It's going to make them honest and put them in a bind."

Johnson averaged career-lows in yards per carry (3.6) and yards per catch (8.9) in 2018, but he said there was no proving ground when Kingsbury arrived. The coach believes in him, and likewise, Kingsbury sees a player confident in his ability to return to stardom.

"He's had a couple tough injuries and some different things that have been unfortunate, but he knows how good he is," Kingsbury said. "He knows what it looks like when he's playing at his best and being utilized in that manner."

While Johnson is confident, he is never complacent. Past coaches raved about his work ethic and Kingsbury has gotten an early taste.

"We don't use him on special teams, but any time there is a lull, he's jogging over, 'Hey, what can I do?'" Kingsbury said. "He's hopping into drills. He's a guy that is always looking to get better. And that rubs off on the rest of the team. His work ethic is phenomenal."

For all of Johnson's talent, he couldn't get rolling in 2017 or 2018. With Kingsbury in the building, Johnson feels like his fifth professional season will turn back the clock.

"It definitely makes me feel like it's getting back to 2016," Johnson said. "I'm very excited. I can't wait for the season to actually get going."