The local hero hit up his old stomping grounds to catch the Game 4 matchup at Rocket Mortgage FieldHouse ... and when Bron, Savannah and his agent, Rich Paul, made their way to their courtside seats, the folks in attendance showed their appreciation for the Cavs legend.

The team even gave James a special shoutout on the Humongotron ... with a brief montage of his Cavs career highlights, including Cleveland's thrilling 2016 NBA Finals win over the Golden State Warriors.

Of course, James has a bit of time on his hands after his Lakers were booted from the postseason in the first round ... so why not check out some of the action??

There's some speculation Bron was doing a bit of scouting, too ... as his future in L.A. is uncertain, and there will always be the possibility he could return home before retiring.

As for his bottle of choice, it was Opus One ... and depending on the year, its price hovers around the mid-hundreds -- but can cost even more.

The wine appeared to feature a special message on it ... although it's tough to read who etched it on the label.

James also had a to-go coffee cup and three bottles of water at his feet during the game ... which ended with the Donovan Mitchell-less Cavs falling short to the Cs, 109-102.

Bron and Co. weren't the only A-listers in the 216 on Monday -- as we previously reported, Khloe Kardashian and her kids were present to support their daddy, Tristan Thompson.