EDEN PRAIRIE, Minn. -- As Chad Greenway suggested Wednesday, the Minnesota Vikings' linebacker competition might not be as open as it would seem at first glance. After bringing rookie Eric Kendricks along slowly in their first two weeks of organized team activities, the Vikings appear to be preparing the second-round pick to start at middle linebacker.

Kendricks was with the first-team defense almost exclusively during Thursday's practice and teamed with Greenway in the nickel defense with Anthony Barr still nursing an injury. In the end, the second spot in the nickel package could turn out to be the only real competition at linebacker in training camp as the Vikings try to determine if Kendricks can stay on the field for three downs as a rookie or if Greenway should maintain a full-time role at age 32.

Rookie linebacker Eric Kendricks has shown plenty of potential, Vikings coach Mike Zimmer said. AP Photo/Ann Heisenfelt

At the moment, the smart bet would seem to be on a Kendricks-Greenway-Barr triumvirate in the base defense to start the season (and yes, you can credit us for coining the 'KGB' nickname for the group).

Kendricks eventually will have to show he can handle the full scope of a linebacker's responsibilities if he wants to play in both the base defense and sub packages as a rookie, but both Greenway and coach Mike Zimmer had good things to say this week about how the rookie has absorbed the defense so far.

"He's further ahead than most rookies, I would say," Zimmer said. "They're all different -- Barr was pretty sharp last year when he came in. Eric's been doing a good job. He's obviously got a lot of athletic ability. He's studying real hard. I think he's got a chance to be a good player."

Zimmer has said he's tougher on the players from whom he expects the most, and he held Barr to an exacting standard as a rookie in training camp last year. He said Kendricks still has times when he repeats mistakes -- something Zimmer harps on his players not to do -- but sounds pleased with the rookie's progress as a whole.

"It's hard for linebackers with alignments and different coverages and different things they have to do, because they're involved in so many different things with the run and the pass. They have a lot of things on their plate, and with a young guy that has to make calls, that has to make adjustments and checks, it will take a little while. But I'm more encouraged by the things he's done."