On Saturday in Maryland, three NBA teams attended a workout with a handful of prospects in their early 20s who recently completed standout college careers and are jockeying for an opportunity in the league.

Towering among the group that day was a 32-year-old who understands some things now about being a professional that he wishes he had known when he was their age.

Hasheem Thabeet cannot change his past, but the 7-foot-3 former Grizzlies center is bullish about his future in the NBA.

"There’s so many things I can believe I can do," Thabeet told The Commercial Appeal in a phone interview this week.

Ten years removed from joining the Grizzlies as the No. 2 overall draft pick in 2009, Thabeet is determined to return to the NBA, even though he is five years removed from his last game in a league that has changed dramatically since he left.

That's why Thabeet runs sprints in the mornings – and sometimes in the afternoons – as he works out up to three times a day in preparation for an opportunity to prove there is still a place for him at basketball's highest level.

DOWNLOAD THE APP: Follow Grizzlies news from the Commercial Appeal on your mobile devices

"The game, as you can hear from a lot of people, the game has changed," Thabeet said. "So I’m trying to catch up and just do a lot of running."

This intense training regimen, which includes the expansion of his offensive game, is indicative of a maturation that Thabeet credits to an understanding he once lacked.

As a rookie just five years into playing basketball, Thabeet found himself – as Tanzania's first NBA player – dropped into a Grizzlies organization expected to make major strides in the 2009-10 season.

There were few veterans to learn from, with Marc Gasol still establishing himself and Zach Randolph only beginning to remake his reputation in Memphis.

"The thing about Hasheem was I don’t think he had a good mentor," former Grizzlies star Tony Allen said during a January appearance on "The Chris Vernon Show." "Didn’t nobody mentor him, like a seasoned vet at the time."

Allen joined the Grizzlies at the beginning of Thabeet's second season with the franchise and made some effort to help the young center.

But by then, the franchise was expected to compete for a playoff spot after a four-year postseason drought.

The patience with developing Thabeet wore thin in Memphis, and the Grizzlies traded him to the Rockets for Shane Battier midway through his second season. It was an unceremonious end with the organization for a player who said he never expected to be drafted by the Grizzlies in the first place.

And it was only after Thabeet left Memphis that, he said, he truly learned to be a professional.

"By my fifth year when I was playing in OKC with Caron Butler, Derek Fisher, Kevin Martin, those were the vets that took me in and actually taught me something," Thabeet said.

Thabeet posted a respectable 2.1 plus/minus rating in 66 games with a 60-win Thunder team during the 2012-13 season. It's a number that he points to with pride as the proof of the impact he still could have on an NBA roster if given the steady opportunities that eluded him for most of his five seasons in the league.

"It’s just that I was very limited with my time spent on the court," he said. "I need that chance, and I need to get back out there. That’s how I feel.”

Thabeet knows defense is still his calling card, but he is working on his offensive arsenal, too, in anticipation of his shot at redemption after his NBA opportunities fizzled after his run with Oklahoma City ended in 2014.

Particularly, Thabeet has been working on expanding his offensive game to the 15-23 feet range.

"One thing that might be shocking people is the past few months and few years that I haven’t really been playing I’ve been working on my shot," Thabeet said. "Just to be able to score away from the basket, rather than just posting up and shooting hook shots."

Thabeet played in Japan for the Yokohama B-Corsairs in the 2017-18 season, averaging 13.1 points, 8.4 rebounds and 2.7 blocks per game. His performance efficiency rating of 23.28 in the Japanese league would have made him a top-25 NBA player if it translated to the NBA.

The competition level in the NBA is much higher, obviously. But Thabeet believes he deserves another chance. And he doesn't mind sharing his experience with younger players also attempting to find their way. He gives them the same advice he would give the younger version of himself about learning what it means to be a professional.

"When I run in to young guys in the league, that’s one of the things I try to talk to them about. So that’s probably the same advice I would give myself is just be a pro. No matter what’s going on, anything outside of the court, whatever. If things aren’t going your way, you’ve just got to be a pro.”

And if the Grizzlies wanted to give Thabeet a workout?

“I don’t have any grudges against that organization," he said.

Reach Grizzlies beat writer David Cobb at david.cobb@commercialappeal.com or on Twitter @DavidWCobb.

COACHING SEARCH ANALYSIS:Grizzlies coaching search, Jonas Valanciunas' future intertwined

GIANNOTTO:What does Marc Gasol's NBA Finals run mean for Mike Conley's future with Grizzlies?

MEET THE CANDIDATES:Who are the seven known Grizzlies coaching candidates?