Randy Moss is 35 years old and the fourth-leading receiver on his team, but Vikings coach Leslie Frazier said he's expecting the potentially dangerous SuperFreak of old when Moss plays his first regular-season game as an opponent at the Metrodome on Sunday.

"They still take some shots with him down the field," said Frazier, whose Vikings play the 49ers on Sunday. "There are times they're trying to get behind the secondary with him. So he still shows that if you blink, he can run by you. He's got that ability. He really seems to be rejuvenated in their offense. He's doing a good job."

Frazier also became possibly the first person ever to say this about the moody Moss: "It seems like he's always motivated to play."

Moss, a starter opposite Michael Crabtree, has five catches for 61 yards (12.2) with a long of 20 yards and one touchdown in two games. He caught only one pass for 14 yards in last week's victory over Detroit. Crabtree (13), tight end Vernon Davis (eight) and receiver Mario Manningham (seven) have more catches than Moss.

"I'm not sure of his role," Frazier said of Moss. "I know on tape they utilize him quite a bit. They bring him in in different packages and he's playing well for them. He's making some plays for their offense."

Where do you start? When it comes to slowing the San Francisco offense, the Vikings are in agreement that it starts with the running game.

The 49ers, a physical team that has a pair of eight-point victories over 2011 playoff teams, have used their sixth-ranked rushing attack to set the tone.

"They establish the running game, and once they do that, it opens up everything for the passing games," defensive end Brian Robison said. "They can play-action off of that, bootleg off of that. So, for us, it's about going out there, stopping the run and trying to make their offense a little more one-dimensional."

The 49ers have run 59 times for 334 yards and two touchdowns in the first two games, a 5.7-yard average that is second best in the league. And it's a multi-faceted attack, even with Brandon Jacobs having missed the first two games. Frank Gore has averaged 6.1 yards per rush running mainly between the tackles while Kendall Hunter has provided a change of pace.

"Hunter is the guy who can bounce outside," Robison said. "He has the speed and the quickness to get outside and make a lot of plays on the edge. And then you have Gore, who wants to head downhill quick. We have to have awareness of which back is in the game, and be able to play off of that."

But that's not all.

"You get so concerned with the run, you fall asleep, and then they go deep on you," safety Jamarca Sanford said.

Close quarters Everson Griffen has been tried at linebacker and has played both defensive end and tackle on passing downs. In Indianapolis on Sunday, rushing from the inside, he got the only sack by a Vikings defensive lineman this season.

So is it harder to pass rush from the inside?

"You can really use your same moves," he said. "You're just in tighter quarters. You just have to make them quicker, and that's the only thing. It happens quicker inside."

Etc. • Linebacker Erin Henderson (concussion) missed practice Wednesday. He will have to pass an NFL-mandated test to be able to play Sunday. Center John Sullivan (ankle) was limited.

• Frazier said the team is expecting rookie receiver Jarius Wright (ankle) to be able to play Sunday.