The pendulum swung to and fro between the pair through three mountain speed tests near Lake Como. Ogier, who realistically must win to stand any chance of claiming a seventh FIA World Rally Championship title, led the Spaniard by 6.7sec.
WRC leader Elfyn Evans was just 0.8sec further back as the Welshman doggedly hung on to Toyota Yaris team-mate Ogier in his quest to seal a maiden championship crown.
The already tight situation at the front after Friday’s first full day became even closer when leader Sordo and second-placed Esapekka Lappi were hit with a late-night 10sec penalty for missing the same chicane in yesterday’s closing Monza test. Just 2.0sec covered the top three as they restarted.
Although much of the snow that blanketed the region melted overnight, there were significant patches across the loop that demanded extreme caution.
Ogier immediately grabbed the lead in the 25.06km Selvino special stage with a stunning fastest time.
Sordo retaliated with victory in the 11.09km Gerosa to reclaim the advantage as Ogier was too cautious. But the Frenchman picked up the pace and was back in front after the morning’s final 22.17km Costa Valle Imagna.
“We didn’t expect the snow,” Ogier admitted. “It was challenging and I really tried to stay in the lines from the cars ahead. The second stage wasn’t good. I was much too careful to try and save my tyres, but overall, we were fast across the loop so it’s a good position.”
Sordo was in no mood to concede defeat. “The first stage was nice. I was careful in the bad parts but was surprised how nice the car was feeling at the beginning. The feeling on the second stage was the same, but on the last one, I lost a little bit. The battle is still on!” he said.
Evans climbed from an overnight fourth to third in Selvino and fended off Ott Tänak’s i20. Fastest time in the final stage provided much-needed breathing space as he returned to mid-leg service in Monza with an 8.2sec advantage over the Estonian.
Lappi could not match the pace of those around him and dropped to fifth in a Ford Fiesta, 18.5sec from the lead. He lost more valuable seconds after sliding into a bank at a final stage hairpin.
Kalle Rovanperä was sixth in another Yaris, the Finn yielding time after losing control in the snow and swiping a wall. The impact knocked his car’s steering out of line and cost more time across the rest of the loop.
WRC 3 leader Andreas Mikkelsen and Oliver Solberg were next up, while Mads Østberg not only wrestled the WRC 2 lead from Pontus Tidemand, but climbed to ninth in his Citroën C3 R5. Emil Lindholm completed the leaderboard.
Thierry Neuville did not restart following his retirement yesterday as Hyundai Motorsport elected to keep the Belgian off the mountain roads, while Ole Christian Veiby dropped three minutes after sliding off and getting stuck on a snow-covered bank.
Full coverage from ACI Rally Monza is available on WRC+ All Live here, including every stage broadcast as it happens as well as key interviews, features and expert analysis from the service park.