In one case, with rookie CB Xavier Rhodes, it meant he was expected to sit out of practice Friday afternoon.
Rhodes suffered what is believed to be a minor hamstring pull Thursday, a practice in which he had an interception during full-team work.
Erin Henderson is solidifying himself as the team's starting middle linebacker, but he is now fighting through a groin injury. He was expected to practice Friday afternoon but it will be an injury to watch.
"He's fine. It was a little sore, but he worked through it yesterday," head coach Leslie Frazier said. "He feels like he can work through it as well."
If Henderson would be limited, second-year player Audie Cole is the next in line at middle linebacker.
"I like how hard he works. He's a bright guy. He plays physical, has length. We just need to keep giving him opportunities," Frazier said.
"We'd have to get those guys some experience that are backing Erin up right now and do whatever we'd have to do if something were to happen with Erin. To say that we'd be pretty satisfied and complete with where we are depth-wise at the middle linebacker position, I couldn't say that today. We'd need to see those guys work."
With the way Henderson has been practicing to date at middle linebacker and newcomer Desmond Bishop is acclimating at weakside linebacker, Frazier said the coaching staff hasn't had discussions about moving Bishop to middle linebacker recently.
Bishop played inside linebacker for the Green Bay Packers in their 3-4 defense but has been used exclusively at outside linebacker in the Vikings' 4-3 defense in his first training camp in Minnesota.
Reserve WR Chris Summers is also dealing with a hamstring injury that was expected to keep him out of practice Friday afternoon.
"So many times it comes down to that one possession in a game and sometimes it is that two-minute drill, whether you're trying to stop a team or trying to score on offense," Frazier said.
Frazier wanted to see the execution and awareness, as well as the sense of urgency, from both the offense and defense. Last year, he said, there were missed opportunities.
"We sometimes would shoot ourselves in the foot with some things we didn't execute as well as we could have," Frazier said.
"We're seeing a guy right now that I think can help our football team and really make a difference for us in the passing game, but he's having a very, very good camp," Frazier said. "His attitude has been great. Watching him get in and out of routes and catch the football, we're expecting big things from him."
Tim Yotter is the publisher of Viking Update. Follow Viking Update on Twitter and discuss this topic on our message boards. To become a subscriber to the Viking Update web site or magazine, click here.