Perhaps it was their 7-9 record last year, or the fact that they haven't made the playoffs since 2012. Or, maybe people stopped taking them seriously when the moribund 49ers beat them 20-3 in the 2015 season opener. Whatever the reason, the Vikings aren't often talked about as a postseason contender this season, and that could be a mistake. After their 28-19 win over the Lions on Sunday, Mike Zimmer's team is now 4-2, and the only loss since that embarrassing opener came to the unbeaten Broncos by a 23-20 score on Oct. 5. The Vikings have been in every game, and things are starting to heat up on both sides of the ball.

AFC South's horrific start could mean big changes ahead for all four teams

Second-year quarterback Teddy Bridgewater has moved past stretches of inconsistent play to look, at times, like a franchise quarterback. Against Detroit's formerly solid pass defense, he completed 25 of 35 passes for 316 yards, two touchdowns and no picks, including an amazing throw-and-catch score to receiver Stefon Diggs, who has become a real factor as of late. Running back Adrian Peterson, who was a bit green in the gills for the Lions game after he allegedly swallowed some chewing tobacco on the flight to Detroit (Peterson countered that report with the revelation that he had a bad reaction to shellfish), managed 98 yards on 19 carries. And it should come as no surprise to anyone who understands Zimmer's particular acumen that the Minnesota defense can be a problem for any opponent. The Lions managed touchdowns on their first two drives, and managed just one field goal through the rest of the game as Zimmer and his staff made adjustments. Six different players combined for seven sacks of quarterback Matthew Stafford, and even when the Lions did move the ball late, it didn't matter—the perfect example of this was the fourth-quarter, 88-yard drive that ended on downs at the Minnesota one-yard line.

The Vikings don't look like potential Super Bowl winners yet, but this is a young team coming together, and if they keep it up, they could find themselves in the postseason for the first time in Zimmer's tenure.

“I'm really proud of this team,” Zimmer said after the game. “To start off [down] 14-3 and come back to score 22 unanswered points and play the way we did in the second half, I thought that was huge. Blair Walsh hitting five field goals. We talked all week long about the reasons we lost the game up here last year, and I think we fixed all of those situations today.”

Inside the first-ever Yahoo! livestream of NFL game with Bills-Jaguars

The problems that set the Vikings up to fail last season have indeed been managed this year. Minnesota's offensive line, which was a sieve in 2014, has been league-average for the most part this season. The formerly leaky coverage has improved, and veteran cornerback Terence Newman, who worked with Zimmer in Dallas and Cincinnati, has been a revelation. The formerly unimpressive and inconsistent receiver corps has improved, and it's been the fifth-round rookie Diggs, not veteran Mike Wallace, who has made the difference there. The most impressive play in the Lions win came with 10:19 left in the third quarter, when Bridgewater threw a deep ball to Diggs, who had already shredded cornerback Rashean Mathis near the line of scrimmage, and then extended his body in the end zone for an amazing 36-yard touchdown. That play put the Vikings up, 22-17, and they never looked back.

The NFC North is still the Packers' to lose, and at 6-0, Green Bay doesn't appear to be ceding the crown anytime soon. But you may want to circle Nov. 22 and Jan. 3 on your calendars — those are the dates for the Packers-Vikings showdowns this season, and the former underdogs appear to be in a far more competitive state now.