Errol Spence Jr. Breaks Down Pacman's Brawl ... Offers Advice

Errol Spence Jr. -- one of the top boxers in the world -- has a tip for Pacman Jones the next time a dude runs up on him ... stop lunging so much!!

We got Spence out at Roscoe's Chicken & Waffles and showed him the tape of Pacman's airport brawl ... and Errol provided analysis and a message to the NFL cornerback to take into his next bout.

First ... the boxer gives Jones props for the "mean right" that put the ABM employee, who police say instigated the fight, to sleep.

Next -- Errol commends Jones for handling business in an airport with no preparation.

But then, Spence keeps it real ... saying Jones needs to stop with the lunging punches -- otherwise HE might be the one takin' mugshots in a…