Defensive end Everson Griffen is among the most-animated players in the Vikings locker room. But Griffen, who recently was voted a captain by his teammates, cranked up the volume a little louder in front of the cameras Wednesday.

Still steaming about how the Vikings played in Monday night's 20-3 loss to the San Francisco 49ers, Griffen let reporters — and any teammates who happened to be within earshot — know that such a performance would not be acceptable this Sunday.

"We are a good team. We practice like a good team each and every day. I don't know what that showing was," he said. "We got Detroit coming up this week Sunday. That's our focus now. San Fran, it was a blow to us. … They're more of a team than we were."

As Griffen continued to speak with reporters, his voice grew faster and louder.

"As a team we prepared too hard to go out there and put a performance like that in," Griffen said. "I feel as a team we're going to come together and we're going to go out there and beat Detroit. I'm very angry right now as you can see, because we prepared way too hard. But we're going to go out there and get it."

After a passionate 2½ minutes, Griffen respectfully ended the interview and walked off.

Later, coach Mike Zimmer, who was terse with reporters and told them he was done talking about the 49ers game, did give a lengthy answer praising Griffen as a leader.

"The players voted him a captain, and he's a guy I'm extremely proud of in the maturation that he's had and the way that he's grown up in a little ways," Zimmer said. "He cares an awful lot about the Vikings."

The next challenge

After the 49ers ran all over them Monday night, the Vikings are preparing for electric Lions running back Ameer Abdullah, who made Chargers All-Pro safety Eric Weddle look silly on his way to the rookie's first NFL touchdown last week.

Improved tackling will be an emphasis this week after the Vikings missed 13 tackles, according to Pro Football Focus, while allowing the 49ers to rack up 101 rushing yards after contact.

"There can't be one guy making the play. It's got to be multiple guys," outside linebacker Chad Greenway said. "That's how you get people on the ground. It's hard to make one-on-one tackles in this league."

Making Zimmer happy

Zimmer is looking for a safety to step up and solidify the spot next to Harrison Smith. But he made it clear Tuesday that second-year safety Antone Exum isn't in the mix, saying, "He's a possibility if he could ever figure out what to do."

Exum wouldn't use his youth or inexperience as an excuse. He said he needs to practice with consistency in the hopes of convincing Zimmer to give him a chance to start.

"I've never lost hope in that," Exum said. "But it's making the head coach happy so I've just got to continue to get better. And if he thinks I still need to be grasping the defense, then I think so, too."

'It's just one game'

Blair Walsh's struggles continued when he missed a 44-yard field-goal attempt against the 49ers. But despite missing six preseason field-goal tries, Walsh said it was "just one game."

"I understand that when people are concerned, or want to pay attention to the misses, I have to face it like a man and move forward … but it's just one game," he said. "I'm taking it seriously and [have] got to put a ball through the uprights."

Banged-up Lions

The Vikings had a full house at practice Wednesday, and suffered no new injuries beyond an ankle issue that didn't keep running back Jerick McKinnon out of practice.

The Lions, meanwhile, are dealing with injuries to a few key players. Defensive tackle Haloti Ngata, linebacker DeAndre Levy, wide receiver Golden Tate and tight end Brandon Pettigrew all missed practice because of injuries. But quarterback Matthew Stafford, who injured his right elbow in Sunday's loss, was a full participant at Wednesday's practice.