Za'Darius Smith, a good player who had the great fortune to be cast aside by what became a bad Packers team, was talking with the Star Tribune a couple weeks ago about whether the Vikings can do the unimaginable and actually win their first Super Bowl.

Not next year. Or down the road. Or someday before uncle so-and-so dies.

This year.

"I could see that," he said, matter-of-factly.

For the record, Smith has been on teams that went 2-4 in the postseason. He went 0-1 with Baltimore, which drafted the edge rusher in the fourth round in 2015. He then went 2-3 in three years with the Packers.

But Smith has been to the doorstep of two of the past three Super Bowls, so he's at least sniffed the grand game more recently than the rest of Purple Nation. Two years ago, the Packers whiffed against Tom Brady at home in the closing minutes of the NFC title game. A year earlier, they reached the NFC title game before suffering a 17-point beatdown from a 49ers franchise that Smith still holds in the highest regard.

"I can go back to when this Vikings team first started practicing during training camp," Smith said. "I really didn't know the team then. But I had a sense of what we could be when the 49ers came in here for those two days of joint practices.

"Practicing against those guys showed me what type of football team we could be."

The Vikings are 9-2 and hold the NFC's second seed. The Eagles are 10-1 and hold the top seed. And yet it's the 49ers, 7-4 and holding the third seed, who are fast becoming the dark horse no one wants to face in the postseason.

Since their embarrassing 44-23 home loss to the Chiefs, the 49ers have won four straight while their defense has soared to the top of the league. The 49ers haven't allowed a point in six quarters, a second-half point in four games, and just blanked the Saints 13-0, ending the NFL's longest active streak of games without being shut out at 332, dating back to 2001.

"They're so explosive defensively," Vikings receiver Adam Thielen said of the 49ers. "They can rush the passer. They're super physical and they play with such energy and are so well-coached.

"You could tell that in the joint practices we had with them. And I thought we did pretty well against them in that controlled setting."

DeMeco Ryans is in his second season as 49ers defensive coordinator. The 38-year-old declined a second interview with the Vikings not long before the Purple settled on the now-37-year-old offensive-minded Kevin O'Connell as their head coach.

While O'Connell has unearthed a new level of leadership from Kirk Cousins — a challenge that felled a few of his previous bosses — Ryans has the 49ers atop the league in yards allowed per game (281.7) and per play (4.69); rushing yards allowed per game (79.5) and per play (3.32); first downs allowed per game (16.5); and points allowed per game (15.7).

Offensively, the 49ers are gaining steam with something old (former summertime castoff Jimmy Garoppolo), something new (trade deadline acquisition Christian McCaffrey) and a mentality that's black-and-blue through and through.

Thielen was asked if he joined Smith in remembering the joint practices with the 49ers as some sort of harbinger of the 9-2 surprise that was to come. He tried to go along with it, but couldn't help but tap the brakes on that narrative.

"Yeah, the joint practices are better than what the preseason games have become," he said. "But, honestly, you never really, truly know what you have from year to year until the real games start."

O'Connell said the joint practices were "a huge thing for us" because it came against a team that had just gone to the NFC title game and was coached by Kyle Shanahan, a coach O'Connell looks up to.

"If you do joint practices with the right team, you can get great work in," O'Connell said. "You can really envision some scenarios, competitive scenarios. And I think the light went on for a lot of our guys."