Green Bay, Detroit and Chicago aren't three of Christian Ponder's favorite American cities.

As a starting NFL quarterback, he's 1-5 in those NFC North towns. His Vikings have been outscored 182-103 while he's turned the ball over 13 times and been benched once. And the one victory, a seven-point escape at Detroit a year ago, featured 14 points on special teams.

Asked to explain why he's 3-2 in the division at home and 1-5 on the road, Ponder said, "I don't know." Then he took a crack at it.

"Road games are tough, in general," Ponder said. "Divisional games, whether they're home or on the road, are tough. So when you combine those things, it's tough for an offense. It's against teams you face twice a year, so they are really comfortable in what they do against you and their schemes against you. And crowd noise is a big factor."

That's not good because the Vikings just left Detroit, where they lost their season opener 34-24, and are heading for Chicago, where they've lost 11 of their past 12 meetings with the Bears.

While compiling his 1-5 road record in the division, Ponder has completed just 53.7 percent of his passes for an average of 155 yards per game. He's thrown five touchdown passes been intercepted 10 times and was benched once (at Detroit in 2011). His average passer rating: 58.0

"For us, it's about not letting those [road] factors affect us," Ponder said. "Watching that film, Detroit has a great defense, but a lot of [Sunday's result] had to do with what we did to ourselves."

Frazier: Ponder OK

Coach Leslie Frazier has publicly reinforced his faith in Ponder numerous times since the quarterback's four-turnover game on Sunday. The most clear-cut vote of confidence, at least for the short term, might have come in a conference call with Chicago reporters on Wednesday.

"His job's not in jeopardy," Frazier said.

Cassel's been there, too

From his experiences the past two years in Kansas City, Vikings backup quarterback Matt Cassel knows exactly what Ponder is going through.

"I think [NFL quarterback] is the toughest job you can possibly have," Cassel said. "From one week to the next, you're either the hero or the goat. You just have to be mentally tough and continue to push forward. It's Week 1. We've got 15 more games to go."

Knee 'felt great'

Defensive tackle Kevin Williams, whose absence was felt as the Vikings struggled to stop Lions running back Reggie Bush between the tackles Sunday, saw limited action in Wednesday's practice. It was his first practice since suffering a severely strained right knee in the third preseason game at San Francisco.

"We went out to see how it felt," he said. "And it felt great."

Williams delayed any predictions about whether he'll be able to play Sunday until he sees how the knee reacts overnight.

"[Thursday] is pretty much the key," Williams said.

Also on Wednesday's injury report as being limited were cornerback Josh Robinson (quadriceps), center John Sullivan (knee) and right tackle Phil Loadholt (knee). Those three are expected to play Sunday.

Two starters — middle linebacker Erin Henderson (heel) and strong safety Jamarca Sanford (shoulder) — are on the injury report but had full practice participation.

Oklahoma State fallout

Williams and starting left guard Charlie Johnson went to Oklahoma State and, yes, they've been hearing about the Sports Illustrated investigation that alleges several NCAA violations, including impermissible payments and benefits to players.

"I wish they paid me," Williams said when asked if he had been paid. "I wish they paid all the college players."

Said Johnson: "I'm waiting for the rest of it to come out. It's false. Well, I can't say it's false. But just me personally, there was no money being handled. I never saw any money. I haven't read the academic part. I could be here for 30 minutes talking about it, but I'm not going to right now."

Quick hit

The Vikings signed Robert Steeples, a rookie defensive back from Memphis, to the practice squad.