Cardinals running back David Johnson takes his turn during Diamondbacks' batting practice on Thursday afternoon (Sarah Sachs/Diamondbacks).

David Johnson didn't want to stop.

The Cardinals running back took batting practice with the Diamondbacks on Thursday afternoon, and despite connecting solidly on a couple opposite field shots, couldn't get a ball over the fence in two rounds worth of attempts.

When he was told a third round in the cage wasn't happening, frustrated resignation washed over his face.

"I just couldn't get one out there, man," Johnson said. "I got a couple (to the outfield), but I needed home runs."

Johnson had a lofty goal of multiple homers, but expectations probably should have been tempered because the last time he swung a bat came a decade ago, when he tried out for – and failed to make – his freshman high school team.

After hearing other Cardinals hadn't fared too well in the cage in past years, Johnson admitted it was difficult to trade in pads for a bat. But the competitive fire always burns, which is why he lamented not going to the batting cages in recent days to knock off the rust.

It's that drive which made him happy to hear the comments from Bruce Arians last week, when the Cardinals coach broached the idea of getting Johnson the ball 30 times per game in 2017.

The number is lofty and could be hard to hit. Furthermore, there are cautionary tales about running backs that declined after getting a heavy workload early in their careers. Johnson, though, has no qualms about high usage.

"I'm still young," Johnson said. "I'm still on my first contract. So I feel I can definitely handle 30 touches. I did it last year, basically, with running the ball and catching it out of the backfield."

Johnson said he didn't feel worn down near the end of games last season, even as he became the clear focal point of the offense. He led the NFL in touches, averaging more than 23 per game.

"I never really got fatigued," Johnson said. "Those tough defense games against Seattle and the Rams, those games might feel a little sore, but that's not until the adrenaline comes down. I never really feel too bad."

Johnson has been such an athletic marvel in his two seasons with the Cardinals that it was fair to wonder if it would translate to the batting cage on Thursday.

It didn't, but Johnson gave himself an out when he feigned outrage at the Diamondbacks pitchers for allowing him to take his first round of cuts without batting gloves or a thumb protector. He improved the second time around, but not enough.

"I really need to work on my hand-eye coordination," said Johnson, who later threw out the first pitch. "I probably struck out more than I hit the ball."

The Cardinals brass doesn't care one iota how well he hits it. They just want him to see him run with it. Johnson is more than ready.

"I just like having the ball in my hand," Johnson said. "Whichever way B.A. can think of doing it, I'm all for it."