Patrik Schick scored a first-half hat-trick as Bayer Leverkusen thumped Bochum 4-0 at home to stay four points clear of Bayern Munich, who won 2-1 at Wolfsburg on Wednesday.
Harry Kane's 21st league goal was the difference in Bayern's victory but Leverkusen continued their stellar record to claim the three points and keep the German champions at bay.
With January's Africa Cup of Nations in mind, Leverkusen manager Xabi Alonso rested several first teamers, including Nigeria striker Victor Boniface.
Schick, handed his first league start in 14 months, repayed his manager's faith, winning and converting a penalty after half an hour.
The Czech forward doubled up two minutes later, slamming in a Jeremie Frimpong cross to make it 2-0. He scored again, this time heading in a corner, just before the break.
Alonso took Schick off to a standing ovation midway through the second-half for Boniface, who scored two minutes after coming on.
"We're happy about that, but it's even more important that we keep doing it into the new year" Leverkusen sporting director Simon Rolfes told Sky.
An undermanned Bayern were made to work to keep pace with Leverkusen, Kane and Jamal Musiala scoring first-half goals to victory at Wolfsburg.
"We were in the red zone" coach Thomas Tuchel said. "Compliments to the players. That was a real tour de force in the second-half."
Playing a second straight time without the flu-hit midfield duo of Leon Goretzka and Joshua Kimmich, Bayern rushed out to a 2-0 lead but were pegged back before halftime by a Max Arnold stunner.
The German champions dug in throughout the second-half against a dogged Wolfsburg side coached by former Bayern mentor Niko Kovac, but held on to claim a valuable three points in what is emerging as a true two-horse title race.
"They're a great team, they've got a great coach" Kane said of Leverkusen after the game, but told reporters "we can't control their game, all we can do is keep pushing them."
"We're not even half-way through the season yet, so we can't focus on them too much."
Elsewhere, Stuttgart rebounded from Sunday's 3-0 loss at Bayern, beating Augsburg at home by the same scoreline to leapfrog RB Leipzig into third spot.
Stuttgart's star striker Serhou Guirassy scored again, his 17th of the campaign, while Denis Undav and Chris Fuehrich also got on the scoresheet for the home side.
Promoted Heidenheim continued their impressive debut Bundesliga season, coming from behind twice to win 3-2 at home with Freiburg.
Eintracht Frankfurt scored two goals in injury time to come from behind and win 2-1 at home against Borussia Moenchengladbach.
Gladbach were on course for victory thanks to a first-half goal from Max Woeber, but the goalscorer was sent from the field with two minutes remaining.
Frankfurt's Aurelio Buta and Robin Koch made the most of the numerical advantage, scoring to turn the game.
UNION BEAT COLOGNE
Struggling Union Berlin won 2-0 at home to Cologne to move out of the German Bundesliga's relegation zone.
Second-half goals to Benedict Hollerbach and David Fofana took Union to their fourth win of their season and only their second dating back to August.
Hollerbach scored with a superb solo effort, blasting into the top of the net while Chelsea loanee Fofana produced a mirror image goal with 12 minutes remaining to seal the result.
Union, who signed off from their debut Champions League campaign in the German capital last Wednesday with a 3-2 loss to Real Madrid, have now won two home league matches in a row under new manager Nenad Bjelica.
The loss leaves Cologne stuck in second-last spot on the table, with just two wins from 16 games so far this season.
"It's clear that in this situation everything is called into question – including the coach" said Cologne manager Steffen Baumgart, telling Sky "it doesn't look good for us."