San Antonio Spurs star Kawhi Leonard has had his share of frustrations throughout the season because of a quadriceps injury. And it seems that Leonard's frustrations may have to extend a bit more.

According to ESPN's Michael C. Wright:

Pop said Kawhi is frustrated and wants to be playing, but he said Kawhi needs to be cleared by Kawhi's doctors.

Leonard's injury situation has been in the news as of late. Several media outlets reported that a rift between him and the Spurs' medical staff might have arisen because of the injury. Truth or speculation, what's clear is that the 26-year-old guard is not comfortable waiting on the sidelines.

His battles with such injuries started out last year in the Western Conference Finals when a sprained ankle sustained in Game 1 forced him to miss the second, third, and fourth games of his team's 4-0 loss to the Golden State Warriors.

This season, Leonard finally debuted on Dec. 12. He was careful with his time on the court, though, averaging 16.2 points in 23.3 minutes per game, before returning back to the injured list in early January.

His absence has been deeply felt by his team. The Spurs have already fallen out of the Western Conference's top eight. They have lost 15 out of their last 23 games and as of this writing, the team is in 10th place in the Western Conference.

On a personal standpoint, the injury definitely broke the momentum that Leonard was on. Over the past two years, he has finished in the top three in the MVP race. He came into the league and slowly worked his way up into establishing himself as a premiere defender. But as his career progressed, Leonard has also developed into a lethal offensive threat as well.