Per that report, Leonard's camp believes the injury is "the result of a series of contusions to the quadriceps" between March 2016 and the end of last season:
"According to multiple sources, Leonard's camp has come to believe the issue has more to do with an ossification, or hardening, in the area where the muscle has been repeatedly bruised, and then an atrophy, which in turn affected the tendons connecting the muscle to the knee.
"The Spurs have always called the injury quadriceps tendinopathy, which is a disease of the tendon that has a degenerative effect on the muscle by keeping it in a constant state of exhaustion."
The treatment for each diagnosis is different, another factor in the growing tension between the team and Leonard's camp. And while the Spurs initially handled the medical decisions surrounding Leonard, he and his camp eventually began seeking outside treatment, yet another factor in the divide between the two parties.
"Kawhi is the same person," a league source told Shelburne and Wright. "The only thing that has changed about him is the people speaking for him now."
"The Spurs feel that they hire the best, that they do it better than anyone else. They deserve to have that reputation and that kind of ego," a source close to Leonard said. "But they're just not very open-minded. They don't like others messing with their players."
Publicly, both Leonard's camp and the Spurs have maintained that the sides are working together.
"I think the Spurs and Kawhi and Kawhi's doctors and everyone around Kawhi is just trying to get him healthy, jointly," Leonard's agent, Mitch Frankel, said. "It's not as simple as what's being written, so it's really just that he's gotta get his quad healthy. He's gotta get his tendon healthy, and that's the focus."
"Our focus for all of our players is to provide them with the very best in player care for their entire career," Spurs general manager R.C. Buford added. "Throughout this process with Kawhi, our goal has been to give him the best care and support available, no matter where that comes from."
Behind closed doors, however, there reportedly is a rift. One person in the Spurs' camp suggested that the team is alienating Leonard. And the Spurs reportedly are concerned Leonard's group is trying to push him to a bigger market like Los Angeles (Leonard's hometown), New York or Philadelphia.
Per the ESPN report, "One source close to Buford said the longtime executive admitted to him that he's constantly losing sleep over how and why the relationship with Leonard has disintegrated."
It's possible that Leonard will return to the Spurs healthy next season and all will be forgotten. But the Spurs have to decide if they want to sign Leonard to a $219 million supermax contract this summer, risk letting him hit free agency after the 2018-19 campaign or trade him this offseason.
For the Spurs, the Leonard situation this season was about as dysfunctional as the team gets. The direction the team chooses this summer will indicate whether the team believes it can repair the relationship.