By triumphing at his home race at Zandvoort last weekend, Verstappen equalled Red Bull predecessor Sebastian Vettel's record of nine consecutive wins, and so victory at Monza will put him out on his own on 10 wins.
Gasly, who won the race with AlphaTauri in 2020, cautioned that achieving success at the Italian venue isn't always straightforward.
"I think this weekend is actually probably the trickiest one for Max," he said. "It's Monza, it's a very different track, you're very low drag.
"Quite a lot of incidents can happen into Turn 1, you have a massive gain with DRS, so if someone is fast enough to stick to your DRS they always could get a chance.
"I'll be surprised if he pulls like a 30-second lead like he can do on some other tracks."
Gasly also praised Verstappen for the way he has approached the 2023 season, calling it "very mature."
"You've got to appreciate what he does because he doesn't do any mistakes," he said. "Even last weekend you can have the faster car and have a lock up and go straight and miss it so. I think he's been very mature in the way that he's taken risks when they were there.
"And you can see it, there were times where last weekend on the wet he wasn't pulling away from the others.
"You know he is faster, he could be faster, but you just know he's got it under control, and he knows when he can give away three-tenths and then not take too many risks, and then really push when things are more stable. So he is very complete and very mature in the way that he approaches it."
With Verstappen and his Red Bull team operating at a high level this year, Gasly believes they could potentially be "feeling invincible" after such a run of success.
"At some point, when you put all good ingredients together, you end up with a good dish," he said.
"Trying to do a good pizza with rotten tomatoes doesn't work. They've got a good base, they got a good car, they've got an excellent driver.
"He is the focus of the team, it's just everything, he is performing at his best exactly at the same moment, which ends up with such a domination. So he's performing at his best, I think the Red Bull car is objectively and definitely the fastest in this paddock.
"They are doing very few mistakes, they are often the best at pit stops. They just are on top of their game, and there is nothing really which seems to unsettle them, especially on his side of the garage.
"But as a driver, he's very talented. You start winning once, twice, a third time, you build up the confidence on top of the skills that you've got.
"And on top of that, you know that every single weekend you come with the fastest car, so it's almost like kind of feeling a bit invincible. And that's a bit where are they out at the moment."
