Veteran outside linebacker Chad Greenway was limited in practice Wednesday after the Vikings used X-rays and a magnetic resonance imaging to examine his bothersome right wrist, the same wrist he fractured during the 2013 season.

"He's got a little wrist [injury]," coach Mike Zimmer said. "It's not a big deal. He's been MRI'ed and X-rayed and we just don't want to irritate it more."

Greenway, who wore a black brace on the wrist, didn't go into specifics about the nature of the injury, which he downplayed. He added that he expects to practice fully again Thursday.

"It's feeling pretty good and hopefully we'll be able to push forward," Greenway said.

Greenway sprained his right wrist during Week 7 of the 2013 season and fractured it in two spots the following week. He did not miss a game in 2013, though he did leave the team's Week 14 loss to the Bears in overtime after aggravating the injury. He did not have surgery after the season.

"I think [Zimmer] just thinks I'm getting old, maybe," Greenway said playfully. "Obviously, when I had the issue with it last year, it makes it a little more [noteworthy], wanting to take care of it. I know what it was like to go through the entire season with it last year, and I don't want to go through that again. I think we did a good job of figuring it all out and getting it taken care of."

With Greenway and rookie Brandon Watts, who has a lower leg injury, watching from the sideline, Michael Mauti was the weakside linebacker with the first-team defense.

Greenway gets green dot

In the NFL, the starting middle linebacker is typically the lone defender who has a radio headset in his helmet, for relaying calls from the defensive coordinator to his 10 teammates on the field. But without a clear three-down middle linebacker, Zimmer said Greenway will be the guy with the headset and green dot on the back of his helmet.

In the past, Greenway has handled that duty in a pinch because of injuries, but this will be the first time he wears the green dot full time.

"I'm looking forward to it," Greenway said. "I enjoy getting the call. I'm the first one to hear it, so you can run it through your brain quick before anyone else. It's been a work in progress, but it's gone very well and I hope it will continue."

Thielen, Smith battle

While the top four wide receiver spots appear to be spoken for, the Vikings have been watching youngsters Adam Thielen and Rodney Smith battle for roster spots.

Thielen stood out at times during training camp, and it carried over into the preseason with five catches for 69 yards. And after a quiet start to camp, Smith has come on strong with big plays in practice. He made four catches for 55 yards last weekend against the Arizona Cardinals, including the game-winning touchdown.

With Jerome Simpson expected to be suspended at the start of the season, there is a realistic chance that both could make the 53-man roster out of training camp.

"They've both stepped up and early, I think Adam was having a more consistent camp, but as we've gone through these last couple of weeks Rodney is really making a move," offensive coordinator Norv Turner said. "Those are decisions that obviously Coach Zimmer and Rick Spielman are ultimately going to have to make, but if guy goes out and makes a bunch of plays, they usually find a way to be on the team."

Peterson excused

Running back Adrian Peterson was excused from practice to deal with a personal matter. Also absent or sidelined by injury were cornerback Jabari Price, nose tackle Linval Joseph and linebacker Gerald Hodges.

Meanwhile, defensive end Brian Robison returned to the field after missing two practices while dealing with his own personal matter.

Vikings valued 20th in Forbes rankings

The Vikings ranked 20th among the 32 NFL franchises in Forbes' annual list of the league's most valuable franchises. Forbes valued them at $1.15 billion.

The Vikings were third among their NFC North rivals. The Chicago Bears were eighth at $1.7 billion. The Green Bay Packers were 13th at $1.375 billion. And the Detroit Lions were 30th at $960 million.

For the eighth consecutive year, the Dallas Cowboys are worth the most of the league's 32 franchises. At $3.2 billion, they are the first NFL team to be valued above $3 billion.