The Hall of Fame pitcher told TMZ Sports out at LAX on Thursday -- some 24 hours before he steps into the booth to broadcast Game 1 of Fall Classic in Los Angeles -- that if he were in Cole and Flaherty's shoes ... it'd be all gas and no brakes.

"The only advice I have," said Smoltz, who's won a World Series before, "is pitch every inning like it's the ninth inning."

Of course, starters traditionally pace themselves during outings ... knowing they'll get about 100 pitches before someone takes their place later on. But Smoltz is making it clear ... the guys should forget pitch counts and simply let it fly -- as it could make the difference between winning and losing.

As for how he'd deal with the two teams' stacked lineups -- Smoltz said he'd try his best to keep base runners as low as possible ... knowing that dudes like Juan Soto, Aaron Judge, Shohei Ohtani and Mookie Betts can hit home runs at any time, and he'd prefer to limit that potential damage to just one run.

Although when it comes to Ohtani specifically, Smoltz said he might just avoid him altogether if the score's within reach ... and walk him.