AUBURN HILLS -- What did Detroit Pistons coach Stan Van Gundy do this week?

Well, he called out Andre Drummond's rebounding, which drew more than a few arched brows from those who regard the young center as the Detroit Pistons' golden child.

He challenged Kentavious Caldwell-Pope for defensive deficiencies after the shooting guard committed a late-fourth-quarter foul which put the Pistons into an overtime session in their preseason opener.

He mentioned that Will Bynum already has missed enough of training camp that it probably has cost the veteran point guard any chance of being in the rotation on opening night, just more than two weeks away.

He had the video crew cut up clips from both preseason games, focused solely on Josh Smith getting back too slowly on defense, and showed them at practice, with the critique that the highest-paid Piston takes off too many defensive possessions.

He watched the response by each and every one.

"You show him eight or nine clips of him jogging back defensively, he sees it," Van Gundy said. "Now, what I understand, and he understands, is that's a habit built over time. It's not going to change tomorrow. And so I've got to stay on him, and he has to understand that I have to stay on him."

He put his team through a shootaround that lasted two hours, 10 minutes before Thursday's game. One player groused about it after the Pistons' listless first half in a 14-point win over the Milwaukee Bucks.

"That's what you get after a two-hour shootaround," the player said.

The next day, as reward for their 2-0 start to preseason, the Pistons went through their longest practice of training camp, four hours in duration.

The upshot is that one game after Van Gundy told media that Drummond's substandard rebounding shouldn't satisfy the player -- a psychologically astute phrasing -- the third-year center had 16 rebounds against the Bucks.

One game after challenging Caldwell-Pope, Milwaukee's shooting guards shot 1 of 13 from the floor, though Van Gundy was reluctant to credit the defense, saying he thought the Bucks just missed open shots.

Two days after Van Gundy said Bynum was falling too far behind to play, Bynum practiced for the first time since a hamstring pull on the first day of training camp.

As if there were any question, the message is getting through.

There is an open competition constantly happening at the Pistons' training camp, and while Van Gundy doesn't like referring to the competition between players for starting jobs and playing time, it is real -- and so is the competition the coach embraces, the internal one a player faces within himself.

Note that Van Gundy didn't criticize Drummond for missing free throws, but for not rebounding like he should.

He didn't criticize Smith for poor shot selection on 3-pointers, but for lollygagging in transition.

He didn't criticize Caldwell-Pope for his greasy-palmed ballhandling, but for ill-timed fouls and not challenging his man defensively the way he can.

He wasn't focused on the things those players did poorly, but the areas in which they should excel and weren't.

If the Pistons who have been here beyond this season thought anything they had done in an NBA training camp previously was difficult, they are learning now that it was virtual mollycoddling by comparison.

They also may become aware that in the effort to change the culture here,

some tough and constructive criticism is necessary, and the biggest names on the roster are not only subject to it, but likely to become its central targets.

In Friday's marathon practice, Drummond was adjudged not to be running hard. So his group had to do the same drill "like nine times, so he was a little upset and the whole thing," Van Gundy said.

The next day, the coach talked to the player about why he coaches him the way he does, which last week included saying Drummond's starting rule is not ensured -- an assertion you can take as seriously as you choose, though it illustrated that Van Gundy isn't handling the franchise centerpiece like a fragile flower.

"They've got to make sure they have an understanding that on things like that, it's not a criticizing, putting them down, you suck kind of thing," Van Gundy said. "It's absolutely the opposite. You're great. And here's one of the ways you can be great: If you run down the floor, you run as well as any big guy in the league, and seal big in the paint, you are unstoppable. And so we have to get you to do that. If you weren't that good, I wouldn't be as concerned about it. I wouldn't care if you ran down the court because we wouldn't be looking to get you the ball anyway. But you have a greatness to you. And so, with greatness and great potential comes great responsibility, and it's our job to get him to do those things."

It's the same message for Smith getting into defensive position, or for point guard Brandon Jennings playmaking for teammates, or for Caldwell-Pope as a perimeter stopper, or Greg Monroe when making the wrong decision as a post hub or a weak finish at the rim, or Bynum for just being available.

Inevitably, Van Gundy said, the emphasis isn't on what a player does poorly, but what he should do well.

"What do you do that's great?" Van Gundy said. "Let's get to that. It's not a matter of do this, don't do that. Let's just get to what you do really well."

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