Gaganjeet Bhullar capitalised on a difficult day for overnight leader Ben Campbell to take control going into the final round of the Fiji International.
New Zealander Campbell had been clear atop the leaderboard in the European Tour event at Natadola Bay, but a five-over par third round of 77 saw him slip to fifth, two shots off the pace.
The Kiwi did manage two birdies on the front nine, but a stretch of four bogeys in five holes, followed by a double bogey and bogey respectively at 16 and 17 left him fighting to stay in touch.
Bhullar, by contrast, equalled the low round of the day on Saturday, the Indian sinking four birdies and carding just one bogey to post a three-under 69 and reach eight under for the tournament.
An all-Australian group of four players, comprising Jake McLeod, Jarryd Felton, Terry Pilkadaris and Andrew Dodt, are tied for second at seven under ahead of what could be a keenly contested final round on Sunday.
Veteran South African Ernie Els, a four-time major champion, was among the players to make a move on Saturday, the 48-year-old matching Bhullar's 69 to sit alone in seventh at five under.