Girona's 1-0 win at Cadiz temporarily gave the Catalan minnows a one-point lead but Real Madrid cruised to victory at the Santiago Bernabeu to reclaim first place, with Vinicius Junior and Joselu also scoring in the rout.
England international Bellingham, the division's top scorer with eight goals, was at his unstoppable best once more in the final third. Ancelotti has shifted the former Borussia Dortmund player into a more attacking role, with freedom to move behind two more central strikers and it has paid dividends.
After scoring a brilliant solo goal against Napoli in midweek in the Champions League and adding two more against Osasuna, the midfielder now has 10 goals across both competitions in 10 appearances.
"Bellingham is finding a lot of chances in attack, he's very involved in the team's attacking play and not having a fixed position gives him an advantage. It's been a surprising start to the season for him in all aspects. Obviously nobody expected this level, in terms of goals," Ancelotti told reporters.