EDEN PRAIRIE, Minn. -- A few observations from the Minnesota Vikings' practice on Wednesday afternoon:

• With Chad Greenway sitting out of team drills because of an injury to his right wrist, Michael Mauti got most of the work with the first team in Greenway's spot. Greenway had a brace on his wrist, but said he hoped to be back at practice on Thursday. The linebacker also will be in charge of the Vikings' huddle this season, coach Mike Zimmer confirmed on Wednesday; the job typically falls to a middle linebacker, but since Jasper Brinkley and Audie Cole aren't likely to be on the field on passing downs, the Vikings gave the job of relaying defensive calls to Greenway because he figures to be on the field most of the time.

• The Vikings continued looking at several safeties next to Harrison Smith, giving Robert Blanton, Chris Crocker and Kurt Coleman work with the first team on Wednesday. They'll continue their audition process on Saturday night in Kansas City, with Blanton -- who missed the Vikings' first two preseason games because of a hamstring injury -- receiving a fair share of the work so the Vikings can evaluate him.

• On a day where the Vikings spent plenty of time with their scout teams on the field, Christian Ponder got much of the work at quarterback, facing the first-team defense for good chunks of the practice. Ponder threw one interception, when Harrison Smith picked off a pass underthrown into double coverage, but made some nice throws the rest of the day. "I think that Christian has improved a lot since we have had him," Zimmer said. "I still like a lot of things that he does, his athletic ability, his intelligence. I keep seeing that he doesn’t have a good arm -- that’s wrong, too. He’s got a good arm. He throws the ball beautifully, he just didn’t make as many plays during the OTAs as some of the other guys did."

• As the Vikings get closer to special-teams coordinator Mike Priefer's suspension at the beginning of the regular season, interim special-teams coach Joe Marciano has spent his time working with Priefer and assistant special-teams coach Ryan Ficken to mold his system into the Vikings' way of doing things. "His system and Mike's system are very similar," Zimmer said. "He’s obviously in all the meetings and everything in with Mike all the time. He’s trying to learn the same terminology that Mike is using that so when we do go to St. Louis (for the season opener) it’s all the same."

• Wide receiver Kain Colter left with trainer Eric Sugarman in the middle of practice, and appeared to have an injury to his right hand.