Kawhi Leonard
Kawhi Leonard is likely to become an unrestricted free agent next summer. In this picture, Leonard #2 of the San Antonio Spurs stands on the court during Game One of the NBA Western Conference Finals against the Golden State Warriors at ORACLE Arena in Oakland, California, May 14, 2017. Thearon W. Henderson/Getty Images

The Toronto Raptors are reportedly signing San Antonio Spurs staffer Jeremy Castleberry seemingly in an effort to keep Kawhi Leonard next summer.

Leonard was traded by the Spurs to the Raptors last month but with the high likelihood of him becoming an unrestricted free agent in 2019, his stay in Toronto may not be for the long term, especially with his interest in playing in his native Los Angeles.

As per ESPN sources, the Raptors are hiring Castleberry to a position in their coaching staff. They will ideally hope bringing him in will sway Leonard toward playing at the Scotiabank Arena for more than one season.

Castleberry not only worked with Leonard in San Antonio, but is also a friend of his, with the duo having played alongside each other in high school and at San Diego State.

Trading for Leonard was always going to be a risk for Toronto. The 28-year-old signaled his intentions of wanting to leave the Spurs in June and was heavily reported to be favoring a move to the Los Angeles Lakers.

However, the San Antonio franchise were demanding too much for a player who had just a year left on his contract and had only played nine games the previous season, so the Lakers opted to seemingly wait another year and keep their young assets.

Instead, the Raptors offered their star player DeMar DeRozan, Jakob Poeltl and a protected 2019 first-round pick in exchange for Leonard and Danny Green last month. Raptors president Masai Ujiri was confident, however, he could persuade Leonard into staying beyond 2019.

"Our team. Our culture. Our city. Our ownership," Ujiri said in a press conference after the signing of Leonard last month. "We have everything here except a championship."

Bringing in Castleberry will definitely help Ujiri's chances in doing so.

Should Leonard decide to stay with Toronto, he is eligible to receive a a five-year, $190 million contract. However, should he test free agency, he could sign a four-year, $141 million deal provided the team have the right amount of cap space as per ESPN.

According to ESPN insider Adrian Wojnarowski, Leonard's preference is still a move to either the Lakers or the Los Angeles Clippers. The former will definitely have the cap space for a deal as they elected to sign NBA veterans on one-year deals following the arrival of LeBron James in preparation for next year's free agency pool.

Interestingly, Bruce Arthur of the Toronto Star reported last month Leonard was already planning his free agency with other players.

"One thing I was told last night is that Kawhi Leonard had already been planning out his free agency for next year and he had already been in contact with other star players in the league and saying 'Hey, where might you want to play with me? What are we looking at?'" Arthur said.

"It wasn't just L.A. he was talking about. Brooklyn [Nets] was maybe somewhere. They're going to have a ton of cap space. That might have been a possibility. So Kawhi has already been thinking ahead to pairing up and playing at a highest level."

Leonard could make his Toronto debut when they host the Cleveland Cavaliers on Oct. 17 in the franchise's first game of the 2018/19 regular season.