Karl-Anthony Towns played 39 college basketball games for Kentucky and lost one, to Wisconsin in the national semifinals. He declared for the NBA draft and was taken with the first overall selection by the Timberwolves.

Everything Towns has done as a rookie has confirmed the wisdom of the late Flip Saunders in taking the 6-foot-11 center over the other viable options to be No. 1.

Yes, Towns has played impressively over the course of 44 NBA games and has lost 31.

On Friday, the Wolves finished a practice and Towns was asked this: Has it been eye-opening to discover the level of difficulty to win in the NBA?

“It has been amazing to see what it takes to win,” Towns said. “You see it every night … how much it takes to win.”

Towns gave a slight shake of the head and said: “At the same time, we have the building blocks here for that to happen.”

Ricky Rubio is 25 and in his fifth season. He was asked about the actual level of difficulty in the NBA compared to what he anticipated when he arrived in 2011.

“It’s tough; there’s a lot of talent at point guard …” he said. “There’s talent everywhere, but for me, it’s point guard. There’s not an easy night, not an easy win.”

Rubio played the Wolves’ entire 82-game schedule in 2013-14. Kevin Love averaged 26.1 points that season. When Love made it clear that he wouldn’t sign an extension, Saunders traded his star to Cleveland in a deal that brought No. 1 overall draft choice Andrew Wiggins to Minnesota.

The Wolves were applauded for that deal, particularly when Wiggins turned into the NBA Rookie of the Year.

One player that trade didn’t help was Rubio. When Ricky was healthy and he had Love to knock down shots, the Wolves finished 40-42. When Love was traded, the rebuilding started again, Rubio severely sprained an ankle and missed most of last season, and the Wolves finished 16-66.

That wound up bringing Towns to Minneapolis and, if he stays long-term, that’s a great thing.

What it means for now, though, is a healthy Butch (Rubio) doesn’t have his deadeye Sundance (Love), and the ever-dwindling legion of Wolves followers is once again finding out how brutally difficult it is to win in the NBA.

This isn’t about winning a title, or squeezing into the playoffs as a 7 or 8 seed. I’m talking here about winning as the happy middle — finishing in the top five in a 15-team conference, getting to a 4-5 playoff series and taking it from there. There’s no league where it’s tougher to do that than the NBA, no question.

“Why do you say that?” Wolves interim coach Sam Mitchell asked.

You can start with pure mathematics:

When two teams play to 100 points, the best team is going to win. When two teams play to three goals, four runs or five scores (let’s say two TDs and three field goals), the odds of an upset are much larger.

And, in basketball, your best players are going to be on the court 75 percent of the time, compared to 35 percent in hockey, less than half the time in football and, in baseball — well, an NBA team faces LeBron James all night, and a baseball team faces Mike Trout five times out of 38 batters.

Plus: You can’t just throw talent at the wall in the NBA and win. First, the talented players have to grow up, and then they have to fit.

“It’s a five-man game, but one player doesn’t change everything,” I said.

Mitchell said: “LeBron James does. If you have LeBron and not much else, you’re still going to win — not a title, but you’ll be in the playoffs.”

True enough. You get LeBron, you can make the Finals (as he proved the first time in Cleveland), even if there’s not much around him.

He’s also the only guy to come into the league in the 2000s about whom you can claim such a thing.

I don’t think Towns and Wiggins and their cohorts are 13-31 because they are being held back by coaching or being hindered in any way in their development.

I think Towns will be fantastic and Wiggins will be outstanding, but they are losing for the simplest of reasons:

The NBA is too tough for a young team with pieces that do not yet fit together. And what might be troubling is that, even with Towns and Wiggins, this roster still could need substantial remodeling before that fit exists.