Unless something goes very right or horribly wrong, Sunday night marked the end of a brief era for Vikings fans: two years with home football games played outdoors.

The caveats, first: If the Vikings defeat the Packers next Sunday at Lambeau Field, there will be at least one more game at TCF Bank Stadium: a home playoff game the following weekend, the reward for winning the NFC North.

Short of that, there doesn’t figure to be another outdoor NFL game in Minnesota for a very long time. Then again, nobody expected there to be a need to play outdoors in 2010. But winters here can do peculiar things, such as cave in the roofs of football stadiums. U.S. Bank Stadium, the new indoor palace slated to open next season, figures to be made of sturdier material than the Metrodome. But you never know.

If Sunday night was the end, it was an appropriate one. With the Vikings vs. Giants game flexed into prime time, one of the coldest days of an unusually mild winter gave way to an even chillier night — testing both the resolve of Vikings fans and the number of purple layers they own.

The train ride in told a pretty good story: After a large contingent of fans headed to the game switched from the Blue Line to the Green Line at the Downtown East station, several of them snapped quick pictures of the billion-dollar stadium looming in the background.

On the train to the game, a young boy asked his mom if she had remembered to pack foot warmers. She replied that she had packed 35 foot warmers. It was going to be that kind of night.

After disembarking the train right outside TCF Bank Stadium, a quick glimpse around indicated that fans had eschewed tailgating. But a more thorough search proved that the heartiest of souls were out in full force.

One group of 20 or so had a TV perched atop their vehicle. Arizona scored a game-clinching touchdown against Green Bay as I walked by; a spontaneous (and unflattering) anti-Packers chant followed. Others threw footballs, even though it was hard to feel one’s fingers.

Ross Smith, a Vikings season-ticket holder for 10 years, exemplified the mood of the night — and of the two years at TCF Bank Stadium in general.

Smith is 36 years old and was born in 1979 — meaning the only era of football he remembers in Minnesota before this time at the U of M was the Vikings’ three-plus decades in the Dome.

He has a child who will be born in a matter of days. That child, too, will only know indoor home Vikings games for decades to come. As such, 2014-15 … “I thought it was great,” said Smith, a Minnetonka native. “It was nice to go enjoy the outdoors.”

But …

“I’ll be happy to go back inside next year,” Smith said.

Indeed. There’s a big difference between tailgating outside and knowing you have a three-hour warmup ahead and tailgating outside before three more hours in the cold.

These two years were a throwback to the Bud Grant Era and a nice novelty for fans who didn’t get to experience it. But it was always going to be temporary, and that’s not a bad thing.