The Hyundai driver delivered a faultless drive in at times tricky foggy conditions to transform his 0.7s overnight lead to a 9.0s advantage over Evans.
While Evans was unable to compete with Neuville, the Welshman remains comfortably ahead of title rival Sebastien Ogier, who could wrap up an eighth crown this weekend if he outscores Evans by six points.
Ogier appears out of contention for the lead some 32.0s adrift, but a resurgent Hyundai of Dani Sordo is breathing down his neck, only 0.2s behind as the battle for final podium spot intensified.
Toyota’s Kalle Rovanpera survived a huge scare on the final stage to maintain fifth overall ahead of M-Sport’s Adrien Fourmaux, who came within 1.7s of notching up a second career stage win.
Oliver Solberg and Nil Solans climbed to seventh and eighth after Gus Greensmith hit trouble on the final stage of the morning.
Heavy fog and a damp road surface greeted the drivers for the opening stage of the day, but it failed to halt Neuville’s charge.
Continuing his pace from Friday, the Belgian chalked up his fifth stage win of the rally to date, edging Evans by 1.7s, extending his overall lead to 2.4s.
“Conditions are much dirtier than expected and the visibility in some places was less than before,” said Neuville. “Not so easy, but we had a good stage.”
While the gap to Neuville was small, Evans felt he was “too careful and just not committed enough” in the stage.
The improving Rovanpera was third fastest ahead of Ogier, who seemed much more comfortable behind the wheel of his Yaris, having battled with understeer and the new Pirelli hard compound tyres yesterday.
“The car is better now and I can trust it,” said Ogier. “I think it will be better today, so I am more happy.”
Ogier’s run eased the pressure he was coming under from Sordo, who dropped 0.9s to the Frenchman.
Neuville threw done a gauntlet to Evans on the next stage, held under blue skies and clear conditions, blitzing the test to chalk up another win.
Crucially he was 4.3s faster than nearest rival Evans, further extending his overall lead to 6.7s, while the latter lost 1.4s to title rival Ogier.
However, arguably the drive of the stage belonged to M-Sport’s Fourmaux, who was only denied a stage win by Neuville, who pipped the Frenchman by 1.7s.
Neuville extended his unbeaten run of stage wins that stretches back to Friday’s Stage 4 on the morning’s final test, but he was made to work hard for the fastest time by teammate Sordo.
In the end, Neuville pipped the Spaniard by 0.2s as the latter heaped pressure on Ogier in the battle for third overall.
Evans set the third fastest time but dropped 2.3s to Neuville as Friday’s early leader struggled to match the Hyundais.
“I’m still struggling a bit with the car rotation,” said Evans. “I just can’t get on the power early enough and hold my line, so we need to work on that.”
While the battle at the front was intense, there was plenty of drama behind as Rovanpera emerged unscathed from a huge moment that went unseen by television cameras.
“We had a puncture on the previous one, so I didn’t want to take any big risks on the cuts,” said Rovanpera. “We had a huge moment on the stage – maybe one of the biggest I have ever had – so we were lucky to escape that one.”
Earlier in the stage, Greensmith suffered a left-rear puncture resulting in the M-Sport driver running on a rim for a large chunk of the test, dropping more than a minute and two spots on the overall leaderboard.
The crews will repeat the morning stages this afternoon before taking in a short blast around a spectator stage at host city Salou to conclude the day.