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You wouldn't know LeBron James was in his 19th NBA season just by looking at the numbers. He's currently averaging 27.6 points per game for the Los Angeles Lakers—the most he's scored in a season since putting up 29.7 points per game for the 2009-10 Cleveland Cavaliers—and he's doing it with an effective field goal percentage of 58.6 percent, his highest total as a Laker. He's averaging more steals than he has since he left the Miami Heat and more blocks than he has since that first stint in Cleveland. If you didn't know any better, you'd say this is just another season of peak LeBron.

But even James knows that this can't last forever. He will turn 37 on Thursday and has spent more than half of his life in the NBA. Eventually, someone else is going to overtake him as the face of the NBA. He's going to decline from superstar status and eventually be forced to retire. LeBron acknowledged that on Tuesday after the Lakers defeated the Houston Rockets. Even if it's something he prefers not to dwell on, he knows that his days as a superstar are numbered. 

"I know I'm on the other side of the hill, compared to the hill I was on before. I know that," James told reporters. "But, I mean, I've thought about it — where I'm at with it. I'm still playing at such a high level, I haven't given it too much thought. But I'm in Year 19 and I'm not gonna do another 19. So I'm definitely not halfway in my career. I'm on the other side of the hill. So, we'll see where the game takes me. We'll see where my body takes me and my mind. As long as my mind stays fresh and my body stays with that, I can play the game. But, in the end, the game will tell you. Your body will tell you. Your mind will tell you. I've put in enough hours and punched enough clocks where, when that time comes, I'll be OK with it."

James has never given an exact timeline on his retirement, though he's dropped some hints in the past. A goal he's consistently mentioned is playing alongside his son, Bronny James, who is currently slated for eligibility in the 2024 NBA Draft. Were the elder James to play a single season alongside his son before calling it a career, he'd have spent a total of 22 years in the NBA. Of course, given his basketball IQ, versatile skill set and increasing comfort playing center in a smaller NBA, James could likely at least contribute to winning basketball a good deal longer. 

Retiring in 2025 would end LeBron's career at the age of 40, but other players have lasted far longer. The oldest player in modern NBA history is Kevin Willis, who played beyond his 44th birthday. There's also the matter of the all-time games played record. Robert Parish, who played until he was 43, owns that record with 1,611 games played. James, who has played in 1,333 NBA games, still has a long way to go on that front. The same is true of Kareem Abdul-Jabbar's minutes record, which stands at 57,446. James, at 50,909 still has several years of work to do if he plans to break that record. 

LeBron could retire right now and go down in history as arguably the greatest player ever. He has nothing left to prove. But he's been a dominant force for almost 20 years, and nothing that has happened this season suggests that he's slowing down. James will continue to play at least as long as he's one of the NBA's best players, and the last few months suggest that's going to last a decent while longer.