CLEVELAND -- As LeBron James' free agency approaches, nobody seems sure what the Cleveland Cavaliers' megastar will do. But while James insists he remains in "championship mode," an even bigger goal is beginning to come into focus.

Speaking to ESPN's Mike Breen, Jeff Van Gundy and Doris Burke ahead of the NBA Finals, James revealed what he believed would be the greatest accomplishment of his already storied NBA career: Playing in an NBA game with his son, LeBron James Jr.

The 4-time MVP made the comment in footage recently released as a part of an UNINTERRUPTED mini-documentary, "Trophies | The Final Face Off," which followed James and Golden State Warriors forward Draymond Green throughout the NBA Finals.

"You want to ask me what would be the greatest achievement of my life? If I was on the court at the same time as my son in the NBA," James is shown telling the ESPN trio in a pre-production meeting. "That would be No. 1 in my lifetime as an NBA player."

As James went on to point out, the idea of one day playing alongside his son, who is currently one of the top 8th-grade basketball players in the country, isn't entirely far-fetched.

"I thought about it because my son is about to be 14 and he might be able to get in [the NBA] a little early," James said.

"And play together?" Breen inquired.

"Or play against," James responded.

Under the NBA's current rules, which require players to be at least a year removed from high school before turning pro, the younger James wouldn't be eligible to enter the draft until 2024 at the earliest. That would require James to play until at least his 22nd season in the league, at which point he'd be 40-years-old.

Plenty, of course, can change between now and then, but at James' current pace, it doesn't appear unfathomable.

For now, James' focus remains on determining where he'll play next season -- and perhaps beyond. His bigger plan, however, is only becoming more clear.

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