"If he works at it on and off the court, he can be a very good NBA player," McClanagan told Filipino outlet The Inquirer.
Sotto is tooling up to join other top NBA prospects Jalen Green, Isaiah Todd and Daishen Nix at the NBA G League 'Select Team' in the Los Angeles area in southern California.
Kai made big strides when he relocated to the U.S. and trained at The Skill Factory (TSF) in Atlanta, and now he's learning with one of biggest names in basketball - one that most people have never heard of.
Rob McClanaghan is the NBA’s most sought-after trainer, helping superstars like Steph Curry realise their full potential.
The Ringer called him "one of the most important behind-the-scenes figures in basketball," the Washington Post writes about how he helped "revolutionise the NBA off-season".
The best in the business hone their skills over the summer with private trainers in closed-door facilities and that's exactly where Kai Sotto is doing now.
McClanagan is impressed by what he sees:
“He is very talented and versatile,” he said after a week working with the Filipino promise.
“He can use both hands well and has a very good mid-range shot from 15 to 18 feet.”
Sotto had his 18th birthday on May 11, and the coach sees lots of space for him to grow his game and improve.
“He just turned 18 so he has plenty of room for improvement and polishing,” continues McClanagan.
“I look at that as a very good thing. If he works at it on and off the court, he can be a very good NBA player. He loves to work out and play and that is always a great sign for someone his age and level.
"The goal is to just improve day by day and take our time.”
Sotto's legion-strong fan base back home is following Sotto's every step towards becoming the first ever home grown Filipino to make it to the NBA, and the big friendly giant's work ethic promises much.
Sotto is prepared to put in the hours at the gym and on the practice court.
In his book 'Net Work - Training the NBA's best and finding the keys to greatness,' McClanagan talks about how megastars like Curry, Durant, Rose, Westbrook, and Love "work to excel at the game."
And in a YouTube video explaining his coaching philosophy, the trainer to big time players says he loves working with kids like Sotto as much as he does with the likes of Derrick Rose.
"I enjoy working out Derrick Rose but I enjoy working out a kid who's just beginning, I like seeing improvement, as long as they're gonna work hard I'm gonna give them my all, I don't differentiate between anybody."
Sotto's off-court progress is just as impressive.
In the same week that Kai's dad Ervin Sotto - who played pro basketball in the Philippines - got his son in with McClanagan, they also signed up to Aaron Goodwin's high-profile sports agency.
Goodwin was LeBron James' first agent negotiating big shoe deals with Nike and helping make him a global star.
Sotto's NBA G League teammate Jalen Green has also signed with Goodwin Sports Management who also have San Antonio Spurs guard DeMar DeRozan on the books.
“Not only does Kai have big-time goals of becoming the Philippines’ first native-born NBA player," says the Instagram post announcing Sotto's joining up with the agency, "he has the drive and skill to match.”
"Kai will be joining @Jalen on the new G League select team for the 2020-21 season 🔥. We look forward to seeing their development and exciting play."
"We look forward to working with Kai and his family," says Aaron Goodwin.
Kai Sotto's NBA dream has become a path, a plan, and it's getting closer by the day.