Popovich: It has been 'difficult' for Kawhi Leonard to get through rehab routine

Leonard has yet to suit up for the Spurs this season

When the San Antonio Spurs announced that Kawhi Leonard would be sitting out the entire preseason to continue rehabbing his quad injury, it was slightly concerning, but everyone just figured it was the level-headed Spurs playing the long game. 

However, as the regular season enters week No. 4, with Leonard yet to suit up, his absence has become more concerning. In particular, there was a video of the All-Star forward struggling mightily to get up a flight of stairs on an airplane.

Kawhi Leonard boarding the #Spurs charter flight for Chicago. #KSATsports #KSATnews pic.twitter.com/Z3lgfQOtMc

— Larry Ramirez (@LRam2) October 20, 2017

Now, we have somewhat of an explanation from head coach Gregg Popovich. 

"He's just coming along more slowly, for whatever reason," Popovich told reporters Tuesday. "It's just been more difficult for him to get through the rehab routine. His body hasn't reacted the same way."

Pop on Kawhi's slow progress: "He’s just coming along more slowly, for whatever reason. It’s just been more difficult for him to get through the rehab routine. His body hasn’t reacted the same way."

— Tom Orsborn (@tom_orsborn) November 7, 2017

The situation hasn't reached DEFCON 1 or anything, but this is definitely troubling -- especially because there doesn't seem to be a concrete reason why Leonard hasn't fully healed yet. It would be one thing if there were a concrete setback, or another injury, but the Spurs don't appear to know exactly why Leonard is struggling. 

For everyone's sake, let's hope Leonard will be back on the floor soon. Without him, the Spurs have still been pretty solid, going 6-4, but they'll be elated once he rejoins the squad.