Following Friday night’s 109-97 loss to the Miami Heat, Timberwolves coach Tom Thibodeau lamented plenty about his team’s defense, including its biggest players’ inability to play, particularly on pick-and-roll plays, with their “back foot up.”

After Saturday’s practice, a reporter asked just what exactly that meant.

Thibodeau paused more than a beat for dramatic effect, rolled his eyes and demonstrated a stance in which he moved his feet from staggered, with one set many inches behind the other, into an even, squared position.

“I thought we went through that in training camp,” he replied.

To reporters and players alike, maybe not.

“If your stance is staggered, you’re opening the gate,” Thibodeau said. “A guy can get by you on the first dribble. If your back foot is up, you’re going to be more square to the ball, so you’re going to contain penetration more.”

If it’s not, the Wolves leave themselves susceptible when the ball shifts direction, leaving them open to not just one man, but two getting beat by dribble penetration. Thibodeau said stopping the ball by squaring up requires discipline, energy and commitment, and it has troubled his team from the start.

“I knew it from the beginning of the season,” he said.

Wolves star Jimmy Butler was less specific, but no less critical after Friday’s game. “We haven’t guarded anybody all year long,” he said, adding: “We’ve got to start guarding somebody. It’s getting ridiculous and it’s getting sad.”

Those woes include defending the pick and roll — where the Wolves have repeatedly been attacked, particularly with the game on the line — and allowing far too many open three-pointers.

The Wolves began last week with Detroit’s Reggie Jackson and Andre Drummond attacking them time and again Sunday, targeting big man Karl-Anthony Towns particularly on the pick and roll in the fourth quarter of a 100-97 Pistons comeback victory.

The week ended with the Heat making 19 of 39 three-pointers — five by point guard Goran Dragic alone — in Miami’s Friday victory.

“We have to do better,” Thibodeau said. “There’s no getting around that. It’s what we have to do if we want to win. We can’t keep talking about it. We have to do something about it.”

That requires both better technique, with that back foot forward among many other things, and better effort that Thibodeau says often requires third, fourth and fifth tries.

The Wolves sometimes don’t get to the second effort.

“It’s just small things we’ve got to be better at,” said point guard Tyus Jones, who played 32½ minutes Friday when starter Jeff Teague couldn’t go because of soreness in his Achilles. “It’s paying better attention to detail, not taking any plays off. There are plays where we’re going what we’re supposed to be doing, but then there are a number of plays we’re taking off. We’re not giving multiple efforts and that’s when we get in trouble. …

“It definitely wasn’t our best performance [Friday night]. I think everyone on the team knows that. So it’s on us. It’s not the game plan or scheme. It’s solely on us putting that effort in.”

Veteran forward Taj Gibson calls it a matter of study and making adjustments.

“They’re going to pick on certain players on our team the same way we pick on certain players on their team,” Gibson said. “It’s a game of chess. It’s all about a whole game of 48 minutes. We just have to put more into it. It comes with effort. It comes with guys watching film and having to sacrifice. …

“One game we’ll do the correct way and one game we’ll slack off. It’s just being consistent. That’s the main thing.”