Lappi ended the morning loop with a 1m24.3s lead over M-Sport’s Adrien Fourmaux, with Toyota’s Elfyn Evans [+1m40.5s] in third after Toyota driver Katsuta’s victory tilt came to an end on stage 10.
Oliver Solberg continued to impress and sat an incredible fourth overall (+2m25.4s) in the WRC2 class lead, while Hyundai’s Thierry Neuville climbed from 11th to fifth overall, 2m42.9s behind team-mate Lappi.
The heavy snow showers that dominated Friday’s action abated on Saturday and were replaced by much colder temperatures.
That the conditions were much more favourable to the front runners was outlined by the returning Ott Tanak, who set the pace on the day’s first test, stage nine [Vannas, 15.65km].
After crashing out on Friday’s stage four, the Hyundai driver started first on the road but was able to pip Evans by 0.3s, as he made the most of a compacted ice layer on the road.
World champion Kalle Rovanpera, also returning from his crash on stage four, was third fastest and just 1.2s adrift of Tanak.
In the battle for the overall lead, Katsuta responded to overnight rally leader Lappi by posting a time 2.3s faster than the Finn to cut the deficit to 0.9s.
“My driving was quite messy, not so good,” said Katsuta.
Solberg continued to head the WRC2 field, but dropped to fourth overall having ended Friday in a stunning third outright.
Neuville climbed back into the top 10 on the leaderboard despite struggling with his i20 N.
“There was a nice ice layer this morning, so it was better to be first today,” said the Monte Carlo winner. “But generally, I have no traction at all. I’m trying but I just can’t brake late and get out of the corner.”
The battle for victory underwent a significant twist in stage 10 [Sarsjoliden, 14.23km] when Katsuta hit trouble while chasing down leader Lappi.
The Japanese lost control of the rear of his GR Yaris and found a snowbank, which fired the car across the road and into deep snow, damaging the front of his car. Katsuta and co-driver Aaron Johnston attempted to dig the car out, but their victory hopes were instantly tarnished.
"I was pushing to gain the gap between me and Esapekka. The conditions were much better today so it was important to push in every single corner," said Katsuta.
"Obviously, I was trying hard and at one corner I came in with a bit too much speed and snapped the rear and then I hit the snowbank with the rear. Then we got stuck in the snowbank.
"It is hard to find the words [for how I’m feeling]."
This took the pressure off Lappi, who emerged from the stage with a comfortable 1m31.6s lead over Fourmaux as Evans jumped up to third. Neuville continued his rise up the leaderboard to sit sixth overall at the end of the test.
It was won by Rovanpera by 2.8s from Tanak, with Evans another second in arrears.
Fourmaux further cemented his second position by winning the final stage of the loop [Stage 11, Bygdsiljum 28.06km] after posting a time 1.5s faster than Neuville. The time helped the Ford driver extend his gap over third-placed Evans to 16.2s. Evans was hampered by snow entering the car's grill which reduced the power from the GR Yaris.
Equipped with a comfortable lead, Lappi backed off, clocking the fifth fastest time, to ensure he preserved his advantage.
“I was safe but I don’t know what else I should do to be honest,” said Lappi, whose only WRC win to date came in Finland in 2017. “The time is what it is.”
The morning stages will be repeated this afternoon, ahead of an evening run through the Umea stage.
