Bayern Munich came from behind for an eighth successive Bundesliga match as the champions overcame struggling Mainz 5-2 at Allianz Arena.
Hansi Flick's side have not taken the lead in a league game since October and might have been staring down the barrel of a second defeat of the season had Danny Latza beaten Manuel Neuer early in the second half.
Mainz had a 2-0 lead at that stage, with Jonathan Burkardt and Alexander Hack scoring in the first half, but Joshua Kimmich and Leroy Sane restored parity in the space of five minutes.
Robin Quaison struck the woodwork as 17th-placed Mainz fought back, though Bayern ultimately had too much.
Niklas Sule's deflected strike and Robert Lewandowski's double – the first of which came from the spot – settling a thrilling contest firmly in Bayern's favour.
Against the run of play, Mainz struck first – Burkardt getting the better of Jerome Boateng and thumping beyond Neuer.
Bayern were convinced Boateng had been fouled, but the VAR disagreed, though Mainz's lead would have been swiftly cancelled out had Finn Dahmen not palmed over Lewandowski's strike.
But Bayern were dealt another blow before the interval, Hack capitalising on some dreadful marking to head home from Daniel Brosinski's free-kick.
Latza should have put Mainz out of sight three minutes after the restart, only to drill straight at Neuer from point-blank range, and the visitors were punished when Kimmich headed in from Lewandowski's flick.
Bayern quickly doubled down – Sane cutting in from the right to curl in a crisp, low finish.
Neuer's crossbar came to Bayern's rescue from Quaison's blistering shot and the hosts made their fortune count as Sule's volley skewed in off a defender a few moments after Leandro Barreiro's own goal was disallowed for Alphonso Davies straying offside.
Barreiro's luck ran out in the 74th minute when he wildly scythed down Serge Gnabry, giving Lewandowski the chance to wrap up the win.
Having sent Dahmen the wrong way from 12 yards, Lewandowski then met Thomas Muller's cross to add a fifth with seven minutes remaining and send Bayern back to the Bundesliga's summit.
What does it mean? New year, same Bayern
Though their habit of going behind in games may soon come back to bite Bayern, who have kept just one clean sheet in 13 league matches, they just had too much power and quality for Mainz on Sunday.
Bayern have recovered 18 points from losing positions in their last eight league outings, and hold a two-point lead over second-placed RB Leipzig, who beat Stuttgart on Saturday.
Lewandowski keeps on rolling
Having capped off a superb 2020 by pipping Lionel Messi and Cristiano Ronaldo to the Best FIFA Men's Player award, Lewandowski picked up where he left off.
He created Kimmich's goal with a deft flick-on and took his penalty in typically composed fashion before sweeping in on the volley late on. He is now on 19 league goals for the season from just 14 games and all three of his attempts were on target.
A mixed bag for Barreiro
Barreiro impressed going forward for Mainz, creating three chances – more than any other player for the visitors.
However, he also conceded possession on 15 occasions – a team-high – and committed three fouls, including a ludicrous lunge on Gnabry, while he was fortunate to not have an own goal to his name, too.
Bayern travel to Borussia Monchengladbach on Friday, while Mainz host Eintracht Frankfurt a day later.