LAS VEGAS – They come to see the stars, fans in record numbers pouring into the Thomas & Mack Center and the adjacent Cox Pavilion this month to get a first look at the NBA’s next generation. But Summer League isn’t for DeAndre Ayton, Marvin Bagley or Trae Young, blue-chip prospects who will come to training camp in the fall armed with multiyear contracts. It’s for Jack Cooley, Scott Machado and Cory Jefferson, who almost certainly will not.

These are the real boys of summer, the grinders using the 12-day audition in the desert to impress NBA executives enough to earn the honor of an invitation to training camp. Take Cooley, 27, the unofficial dean of NBA Summer League stars. This is Cooley’s sixth stint in Vegas. He’s a member of the Phoenix Suns now, a teammate of Ayton’s. Before that he was a Sacramento King, setting screens for De’Aaron Fox, and before that a Cleveland Cavalier, throwing outlet passes to Andrew Wiggins.

For Cooley, this was never a dream. In 2009, he chose Notre Dame, not for a springboard to the NBA, but because it had a top business school.

“I used basketball to get the best education,” Cooley said.

But when he graduated, NBA teams called. Some 18 brought him in for pre-draft workouts. When he went undrafted, he started getting invitations to Summer League.

“I remember my first year I was struggling to remember all the plays,” Cooley said. “Now my sixth year, this is the most complicated offense I’ve had, but it’s second nature, basic easy stuff. It’s a lot easier to understand.”

Cooley is a realist. He’s not a stretch five — he made one three-pointer in four years with the Fighting Irish. He’s not an athletic freak like Ayton, either. He’s a banger, a grinder, and he chose to join the Suns Summer League team for that reason.

“The Suns have scorers,” Cooley said. “They have Devin Booker. They need guys who can make Devin Booker’s job easier. I can be a guy that does that.”

For every Ayton, there are half a dozen Cooleys. There’s Justin Harper, with the New York Knicks. Casper Ware, with the Portland Trail Blazers. Brady Heslip with the Memphis Grizzlies. There are no paychecks for playing in Summer League. There’s per diem, around $100 per day. There’s a hotel room, two-hour practices, daily bus rides and no guarantee of playing time.

“It’s a grind, man,” Machado said. “Every time you come out to Summer League, everyone is trying to prove themselves. Me, trying to facilitate, sometimes you overthink it. Every time you come back, you think, ‘Man I did this already.’ It’s a constant grind and constant pressure you put on yourself.”

For most, Summer League leads to very little. Cooley has barnstormed through the G League with a couple of pit stops overseas. Machado, 28, has made the G League rounds, too, punching his passport in Estonia, Germany, France and Spain along the way. The lifestyle comes with a cost.

“You’re basically living out of a suitcase,” Machado said.

Holidays are spent in cheap hotels. Machado was overseas for his mother’s 60th birthday. Basketball becomes your life.

“I used to have a best friend, but things fell out because of travel,” Cooley said. “I have good friends, but no best friends. It’s hard. Players can make a lot of money but you miss out on a lot, too.”

Yet when an NBA team calls with a summer offer, few turn it down. Cooley could. He graduated with a degree in business finance. He could have earned $90,000 a year working a desk job. He’s had offers to join NBA teams’ front office. Instead, he’s played for less than $30,000 in the G League. Machado, too. He has a degree from Iona, and admits he’s thought about getting into coaching or player development.

The NBA dream still fuels them. All of them. In 2015, Cooley was putting up monster rebounding numbers for the Idaho Stampede, Utah’s G League affiliate. The Jazz noticed, awarded Cooley with a pair of 10-day contracts and eventually signed him for the rest of the season.

“I was sobbing uncontrollably,” Cooley said. “I remember, I had just broken the G League record for rebounding. And I said to my agent, ‘If this doesn’t get me called up, I give up.’ A few days later, I got the [second] call-up. Even now it gets me a little choked up.”

As Summer League winds down, most of the boys of summer will disperse. Some will sign on with G League teams, to maximize exposure. Others will ink European contracts, where the money is better. They will ride buses to small towns in the U.S. or live in isolation in far-flung cities around the world. They will do it, and they will hope for an invitation back to Las Vegas next summer, for the opportunity to impress once again.

“There’s only about 1% of me that thinks about not playing,” Cooley said. “This life is pretty intense. But I love it, I’m glad it’s not easy. Not playing would be a terrible itch that I wouldn’t be able to scratch. I know once the time comes, I will definitely be a part of the game, because I’ll go crazy if I go cold-turkey out of basketball. But right now, I’m a player. The body of work I have put together has caused a pretty good stir here. I believe I’m an NBA player. I believe I can play in the league for a long time.”

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