Spain's Adrian Otaegui leads the 2022 Estrella Damm N.A. Andalucía Masters by six shots after posting a third-round 64.
Otaegui carded eight birdies and one bogey on Saturday to head into the final round on 16 under par, with countryman Angel Hidalgo and Swede Joakim Lagergren his nearest challengers on ten under.
Home hope Hidalgo delighted the bumper crowds at Real Club Valderrama with a tremendous closing birdie to sign for a 70 which contained four birdies and three bogeys.
Lagergren, meanwhile, made an eagle, five birdies - including four in a row from the 11th - and three bogeys in his 67.
Australia's Min Woo Lee was another shot back in fourth, two ahead of fifth-placed Robert MacIntyre.
Otaegui held a share of the lead at the halfway stage but hit the front on his own thanks to birdies at the second, fourth, fifth and sixth.
He dropped a shot at the seventh but got it straight back from 13 feet at the eighth to lead the way at the turn.
Otaegui had to wait until the 16th for his next birdie but after holing from more than 12 feet there, he closed his round with further gains on the 17th and 18th to sign for a 64.
He said: "I’m very happy, everything went perfectly today. I putted well, I felt very comfortable. The crowds were pushing amazingly, so that was unbelievable.
"I had a very good start with a nice birdie on the second and then three birdies in a row at four, five, six and that gave me a bit of momentum.
"I felt good on the course, tried to enjoy it, tried to stay focused. I missed a couple of birdie putts at the beginning of the front nine but finished with three good birdies."
Fellow second-round co-leader Hidalgo got off to a strong start, slotting in his 16-foot putt for a birdie at the second before making a couple of confident par putts.
After bogeying the seventh, the 24-year-old got the shot straight back at the eighth before somehow escaping with a par on the ninth after getting into significant tree trouble there.
He then sandwiched a birdie at the 13th between bogeys on the 12th and 14th before converting his 11-foot birdie putt on the last to get to ten under.
Hidalgo came into the week 130th on the DP World Tour Rankings in Partnership with Rolex but has put himself in a brilliant position to climb up the charts.
Lagergren reached the turn in 36 after carding two bogeys and one birdie on the front side but caught fire down the stretch, reeling off four birdies on the spin at the 11th, 12th, 13th and 14th thanks to some lengthy putts.
He then recovered from a dropped shot at the 16th with a 21-foot eagle from just off the 17th green.