Doc Rivers marvels at LeBron James’ longevity.

One of the most impressive, and somewhat baffling, things about LeBron James is his durability and longevity. It seemed as though he may have been on the decline physically during his last year in Miami and first year back with the Cavaliers. Yet now that his back pain has been reduced, he is still moving around on the court like he did in his younger days.

Prior to Friday’s win over the Clippers, Doc Rivers was asked what the difference is between 23-year-old LeBron and the player he is today.

Via ESPN’s Dave McMenamin:

"I don't see a difference except for he's smarter. I'm amazed, really. We were laughing about it, it wasn't so funny to us watching film. Most players when they get to his age are smart enough now they see everything. But usually when they get to that age, they're too old to do anything about it. Kevin McHale had that comment. ‘If I had the knowledge now but my body at 22, I would have been the greatest player of all time.' LeBron has the knowledge of all those years and he's still top two, three athletic in the league. He has both going for him. He can beat you with his brain, he can beat you with his power. It's a daunting task when you watch him on film."

This season LeBron is averaging 28.9 points per game on a career-high 58.5 percent from the floor. He has also matched his career-best percentage from the free throw line at 78 percent and his 40 percent shooting from behind the arc is the second highest marker of his career.

As he ages, there have been new wrinkles added to his game. LeBron has adapted to being the sole ball-handler for the Cavs often this season and has prioritized developing his jump shot over the last two summers. At some point his athleticism is going to decline. But with the work he’s put into his jumper, as well as the bag of tricks he has in the post, his ability to put the ball in the basket isn’t going anywhere anytime soon.

LeBron’s biggest rival has been the history books, and he continues to add unprecedented chapters as he goes along. As Rivers pointed out, dealing with LeBron is still a daunting task even in his 15th season.