The Cardinals' top two draft picks -- tackle D.J. Humphries (74) and linebacker Markus Golden (44) get work on Field Two during Thursday's OTA.

Bruce Arians loves the potential he sees in the rookie draft class, but when it comes to the 2015 season, the more operative 'P' word is production.

The Cardinals are built to win now, and their coach is willing to give a role to a rookie who can contribute positively to that end goal. Until that time, he will stick with the players who have proven it before.

Arians was asked earlier this week about the rookie he's most interested to watch compete for a starting job. He pumped the brakes quickly.

"Not any of them, really," Arians said. "The roster is so strong right now. It's not like we drafted any of them to start."

It's hard to keep high picks off the field without riling up a fanbase, but Arians is clear his rookies must earn playing time.

First-round pick D.J. Humphries hopes to overtake Bobby Massie for the starting right tackle spot, but at this point, that seems far from a sure thing.

"Everybody gets guys drafted in their position," Arians said. "That's (Massie's) job. Somebody's got to take if away from him."

Arians said Humphries was progressing "slowly" on Tuesday, and that "he needs to mature a little bit." The 21-year-old out of Florida agreed and said he's "taking baby steps right now."

"To be honest, it's pretty freakin' hard on the O-line," Humphries said. "Coach says it all the time: They taught us to block looks in college and here we're blocking concepts. You've got to know that if a defense shifts, you've got to make this call or that call. If your center makes a call, what's your assignment change? There's a lot of stuff that goes on before the ball's even snapped and it's difficult to learn. But I can say I'm getting better every day. My mind is getting a bigger grasp on it every day and it's becoming a lot easier."

The Cardinals have split their 90-man roster onto two fields during OTAs, the starters on one and mostly youngsters on the other (the second field is also a good place for developmental players, as defensive end Matt Shaughnessy and linebacker Kareem Martin have been there as they learn new positions). None of the draft picks has made the permanent crossover to get snaps with the veterans, although third-round pick David Johnson made a brief foray earlier this week, albeit because of an injury.

"It was definitely a little head-rush, a little anxiety heading over there," Johnson said. "After the first play I calmed down

a little bit."

Johnson said this is the natural progression for the rookies, harkening back to his early years at Northern Iowa when he had to fight for playing time. He said joining a playoff team like the Cardinals makes it tougher to find a substantive role initially.

"I'm really going to have to know what I'm doing," Johnson said. "With them winning so many games, I'm going to have to come out and compete, make them believe that I'm ready to play right away and I won't make them lose a step."

The rookies are not trying to rush the timeline. While they want to play significant roles when the season starts, the biggest key now is to fully process the information getting crammed into their heads each day.

"You've got to embrace the process," fourth-round pick Rodney Gunter said. "You can't rush greatness. Greatness does not appear overnight."

The veterans have a significant advantage right now because they've been in the scheme for as many as three years and are comfortable with the verbiage and their responsibilities. While the rookies hope to soon compete with them for snaps, they're also in student mode.

"You've got to understand, guys like (linebacker Lorenzo Alexander) have been here," second-round pick Markus Golden said. "Whenever a play is called, he knows exactly what to do. You've got to get help from those guys. They do a really good job of helping us out. I want to keep getting better."

As Golden goes through the position drills each day, he's convinced the physical tools are there to make an impact on the NFL level once he catches up mentally.

"There are a lot of great players over there (on Field One), but I'm great, too," Golden said. "I know that once I can learn these plays and get over to that field, I'll be able to compete with whoever is over there."

The trick is getting there.

"It's kind of an anxious thing," Humphries said. "You've got to be patient and wait your turn. When we're watching film and I see them over there, I always want to be over there. These are the guys we've been watching on TV for years. You want to get over there and test your ability, but you've got to really master that second field first."