LAS VEGAS — Day 2 of training camp for the U.S. Men’s Senior National Team saw the squad’s first action against the Select Team. And the media walked in to see the young guys finish off a 22-6 quarter to close practice.

The Select Team actually started practicing on Sunday, so they’ve had an extra day together. Their job is to prepare the Senior Team for how opponents will play them at the World Cup. Only three of the 17 players on the main roster have played FIBA basketball on the senior level. So part of the agenda for this week is getting players used to the rule differences and style of play.

Offense: The ball shall move

The biggest rule difference is the lack of a defensive three-second rule. That could be advantageous for the U.S., with two of the league’s best rim protectors — Brook Lopez and Myles Turner — potentially on the roster. But it will also make it tougher to get to the basket on offense than guys are used to.

So the Select Team was crowding the paint on Tuesday. The staff has also showed the players film from previous tournaments to emphasize the lack of driving lanes.

“There’s not as much freedom to get down the lane,” Joe Harris said Tuesday. “A lot of teams are going to be overloading and packing it in, and you got to be able to knock down shots.”

That obviously helps Harris’ chances of making the World Cup roster, even though the league’s leading 3-point shooter from last season (47.4 percent) wasn’t on the Senior Team roster until Monday. Harrison Barnes (27th at 39.5 percent) is the only other player on the 17-man roster that finished the top 40 in 3-point percentage.

New U.S. coach Gregg Popovich wants the ball to move. This team has a “point-five-second rule” on offense, where players shouldn’t hold the ball for more than half a second before doing something with it. Every half of a second where the ball is held makes it tougher to get a good shot. (The FIBA shot clock is the same as it is in the NBA — 24 seconds, with a reset to 14 after an offensive rebound.)

All for one. We welcomed the USA Select Team stars to #USABMNT practice this afternoon. pic.twitter.com/Mgb9yfpY16

— USA Basketball (@usabasketball) August 6, 2019

Mason Plumlee is one of the three guys here who played under coach Mike Krzyzewski for a previous version of the Senior Team. And the emphasis on ball movement is also about the new coach.

“Coach K ran a lot of the stuff we ran at Duke,” Plumlee said. “Pop is definitely San Antonio-style of play where it’s no-hold basketball. You’re moving it.”

It’s also about the make-up of the roster, which doesn’t include any of the 15 American players who averaged at least three isolation possessions per game last season.

“In the past,” Barnes explained, “the one-on-one talent itself has been so potent — Kobe, LeBron, Durant, Carmelo — guys can go out there and get a basket. This year, with the experience that other teams are going to have over us, how hard we play is going to have to carry the day.”

For Barnes, camp has had a much different feel than when he was preparing for the 2016 Olympics with a very different group.

“In ’16, I was one of the younger guys on the team,” he said. “It was more of a veteran team. People knew how to play. They had already been through the system and the pipeline. It was more so just make sure you’re in shape, make sure everyone’s healthy, and just go out there and play.

“This time around, it’s much more structured. You can tell that Pop really wants to put his imprint on USA Basketball. With how the young the team is, the teaching is much more the emphasis.”

Defense: Stay at home

Defense might require a bigger adjustment for some of these players, because they’re used to certain principles with their NBA teams and will have to put those aside to defend (and call out coverages) according to the U.S. Team’s standards. The staff is anticipating a lot of pick-and-rolls from their opponents, and they want to defend those pick-and-rolls with just two defenders.

“We’re doing some different stuff on defense,” Plumlee said, “to try to guard the pick-and-roll with two players and stay home with shooters.”

And Popovich hasn’t hesitated to take these NBA vets back to the basics. Both Barnes and Harris mentioned the “shell drill,” used to work on defensive positioning with the movement of the ball.

Best way to build chemistry

But there hasn’t been too many drills. The first two practices have featured a lot of scrimmaging. On Monday, it was the 16 healthy Senior Team guys split into two eight-player squads, and on Tuesday, the Select Team was brought in.

With only 21 days of training before the first World Cup game (vs. the Czech Republic on Sept. 1), there’s not much time to build chemistry between guys who aren’t used to playing alongside one another.

“You can script and walk through stuff,” Plumlee said, “but playing is the best way to get a feel for your teammates.”

“It’s all new for everybody,” Khris Middleton added. “The first thing is to learn the principles. Try to learn each one of these guys out here. In order to accomplish our goal, we got to figure out things quickly and try to get on the same page as soon as we can.”

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John Schuhmann is a senior stats analyst for NBA.com. You can e-mail him here, find his archive here and follow him on Twitter.

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