Week 3, Pittsburgh lost to Philadelphia 34-3.

The Steelers were done. Until Week 4, when they beat Kansas City 43-14.

The Chiefs were done. Until their next game, when they won at Oakland, 26-10.

The Raiders were done. Until their next game, when they beat Jacksonville 33-16 for their first 4-0 start on the road since 2000.

"I think we'd all like to play at the same level each and every week," said Vikings safety Harrison Smith.

But …

Unfortunately, that whole human-beings-aren't-perfect thing ultimately gets in the way. At least it has for every team in NFL history except the 1972 Dolphins.

But there's another part of human nature that many fans underestimate during the handful of days pouting between a beatdown and their favorite team's next stroll to the plate. Unless it's Cleveland-weak, that favorite team tends to bring a bigger, angrier, more determined bat to the next three-hour scrum.

"We're all professionals, but there might be something more you bring [into the game] when you get that kind of loss," Smith said. "It just feels kind of like you're in a corner, even though you may not be."

At 5-1, the Vikings are hardly in a corner as they head to Chicago for Monday night's game against the 1-6 Bears. Unless, of course, the corner happens to be one game up on the NFC North and tied with Dallas atop the NFC.

It only feels like the Vikings are cornered because of how odd and out of character Sunday's 21-10 loss to Philadelphia was. The Vikings had four takeaways, including two in the red zone, and still lost by double digits as the host Eagles hit Sam Bradford 13 times, sacked him six times and recovered two of his four strip-sack fumbles.

"It's definitely a different feeling," right guard Brandon Fusco said. "You definitely want to play the next game right away after a loss, especially one like that. We're dying to get back out there and show people what kind of team we are."

Or were just two weeks ago.

According to Fusco, the urgency isn't to silence the proverbial critics.

"I don't really know what people are saying," Fusco said. "I barely get on Twitter or Facebook. I stay off all that stuff. Too much media stuff. If you start reading too much of that stuff, it crawls inside your head."

You don't have to tell Bradford. It took about three hours on Sunday for public perception to change gears on him. He went from surprising MVP-frontrunner Sam Bradford to same-old sub-.500 Sam Bradford.

"That's pretty much why I don't pay attention to it," Bradford said. "Whether things are going good, things are going bad, I'm usually the same person. … We all realize we have a lot of work to do. It all starts with me. I've got to go out on the practice field this week, be sharp and lead these guys."

The Vikings are 5½-point favorites, so Bradford is expected to have some extra-motivated assistance in Chicago.

Just like Ben Roethlisberger had when the Steelers went from three points against the Eagles to 43 against the Chiefs. Just like Alex Smith had when the Chiefs went from their 29-point loss to their 16-point win at Oakland. And just like Derek Carr had when the Raiders went from ugly home loss to an atypical easy East Coast road win.

"It's human nature," said offensive coordinator Norv Turner, when asked if players tend to play with more intensity and focus after a particularly lopsided loss or meltdown along the lines of what happened with the Vikings' pass protection last week. "But I always look at the tape in terms of getting ready to play [the next game]. Our guys played hard. They just didn't play as good as they've been playing."

And they're looking forward to bringing one of those typically bigger, angrier and more determined bats with them to the plate in Chicago.