MANKATO – Perhaps the three loneliest words in sports journalism are "I don't know."

Those words were used by a reporter recently when a Vikings fan wanted an answer to the age-old question, "How are the Vikings going to do this year?!"

It was an experiment to see what would happen if a sports journalist actually gave the answer that we all know deep inside to be the truth: "I don't know." None of us does.

Besides, when a fan asks that age-old question, it usually means, "I'll give you 4.2 seconds before I shout you down with my thoughts on how the Vikings will do this year!!" So the words "I don't know," politely repeated a few times, were a nice curveball that left this particular fan frozen at the plate, the bat still on his shoulder.

Expressing the same patience about individual players can leave people equally unsatisfied, especially the young crowd that solves life's biggest problems 140 characters at a time.

Based on one well-blocked 62-yard punt return in Sunday night's Hall of Fame game, Stefon Diggs is no longer a rookie fifth-round draft pick. He's Deion Sanders, and he shouldn't have stopped running until he had hopped the fence and reached the bronze bust room next door.

Meanwhile, poor Trae Waynes. The rookie had a terrible NFL debut on Sunday. It was so bad that, well, his career is over. He's no longer the 11th overall draft pick. He's a bust and it sure ain't bronze.

Or perhaps he's just a rookie who was learning how to play in the first of five preseason games. A kid who needed three yellow flags thrown at his feet on national television to help him understand what coach Mike Zimmer has been preaching for weeks.

"The whole time when I've been talking to him [in practice], I'd say, 'You can't do that. That's a penalty,' " Zimmer said Tuesday. "So it was good for him. [In practice,] he'd say, 'Huh?' and I was like, 'Yeah.' They call it different in this league than they do in college football."

Waynes was flagged twice for holding and once for interference on a 38-yard pass. One of the holding penalties was declined because Wayne's man still ended up with a 35-yard catch.

"I had to learn first-hand," Waynes said Tuesday. "And that's what happened. You got to look at every game as a learning experience, and fortunately it was the preseason. I know this is a different league, a different level. I'll make adjustments."

Zimmer shouldn't have to say it after the first preseason game of a guy's career, but he did say there are no "issues" to worry about with Waynes. He said Waynes reverted back to some college habits and was fine after the game. So come down from the ledge, people.

"He had the one [play] where the guy gave him a little lean outside and he hit bit hard on it," Zimmer said. "That does not bother me at all. I'd rather have him bite on it than be scared. He's got a chance to be a very, very good player."

Will he become a very, very good player? At this point, let's answer that one with the three loneliest words in sports journalism.

As for the Vikings overall? Well, based on the preseason hype, they should pretty much expect to parlay the extra preseason game into the league's first 24-0 season. To suggest otherwise in mid-August could draw finger-pointing, stone-throwing and shouts of "Blasphemer!"

The sense here is the Vikings are on the rise. But so too is their schedule, which could become an issue for a group that went 7-9 without beating a team with a winning record last year.

There's also a lot to like about Teddy Bridgewater. But the Hall of Fame has yet to enshrine a 22-year-old quarterback with six wins in 12 starts.

The offensive line could be good, but it also has a bouquet of question marks that get overlooked way too quickly. The defense could be very good, but let's wait until it can stop the run before we call Alan Page for his reaction. And Zimmer could become a wildly successful coach, but let's see him beat the Packers at least once before we clear space next to Bud in the Ring of Honor.

In other words, we all could take a deep breath, tone down the hype and admit we don't know how the Vikings will do this year.

Mark Craig • mcraig@startribune.com