Gumberg gave the shot back at the third but then birdied the par-five sixth to return to 18 under. Campillo was briefly ahead again after a birdie at the eighth but then bogeyed the next two.
A four-over-par front nine ended Frittelli's challenge but Gumberg marched on with a birdie at the 11th, Campillo responding at the next two cut the gap back to one.
Marcus Armitage picked up a birdie at the 12th, his fourth of the day, to reach 16 under and third place on his own, while Adrian Otaegui set the clubhouse target at 15 under with a bogey-free 64, featuring an eagle at the 12th in addition to six birdies.
Home favourite Wenyi Ding was one shot off the lead after an outward nine of 33, but then made three double-bogeys in four holes to drop back into the pack. More problems were to be found after the turn in general, with Ugo Coussaud mixing three birdies and four bogeys in an adventurous back nine.
Three straight pars for both of the leaders set up a duel over the final three holes and as birdie putts continually refused to drop, their scores remained unchanged as Gumberg safely closed out the win with a well-judged up-and-down at the last.
“Jorge played unbelievably," he said. "He was hitting some amazing shots down the stretch, definitely applying the pressure to me.
“I felt that pressure but we just said, ‘keep doing our own thing, keep our head down and keep going, and it’ll all work out how it’s going to work out and there’s nothing we can do to change that’.
“So he played unbelievably. And so did Dylan too, he had a rough day today but from the first tee onwards it was pressure and ‘go time’.
“Every time I hit a good shot, they hit a good shot. Every time I made a good putt, they made a good putt. So it was a nail-biter to the end, I’m really happy I came out on top but they’re phenomenal players and I expect to see them in this situation very soon.”
