Bayern Munich forward Thomas Muller says his side's return to Bundesliga action after the international break will be "decisive" in their quest to retain the title.
The champions begin a sequence of eight fixtures in the space of a month with a difficult trip to Schalke, where they will face a side who have not won in their last six matches in all competitions.
Schalke, though, have lost just once at Veltins Arena in the league this season, and Muller expects Andre Breitenreiter's side to be hungry for a scalp.
Muller told FC Bayern TV: "They will have their backs to the wall at home in front of their own fans.
"There are easier fixtures coming off the back of the international break.
"We have to take all three points. We are entering a decisive phase in the season."
Bayern will be without midfielder Thiago Alcantara, who picked up a knee injury during Spain's 2-0 friendly victory over England and is expected to be out for four weeks. He joins Franck Ribery (ankle), Mario Gotze (hamstring) and Juan Bernat (groin) in the treatment room.
Schalke coach Breitenreiter welcomed 10 internationals back to his squad with no new injury problems, but he will be unable to call on midfielder Johannes Geis, who is suspended for the visit of Bayern.
Breitenreiter conceded his side would need to be at their very best to claim a result against Bayern, saying: "We have to play with heart and passion. We need to try and have a faultless match.
"FC Bayern are one of the best teams in the world, with a lot of individual quality. Every mistake will be punished.
"It is absolutely necessary against Bayern that we can use our opportunities. We will have some chances and we want to use them.
"The fans will see players on the pitch who will give their hearts into the game. The team will play with passion and they'll try to implement our plan in the best possible way."
Following the announcement that matchday security at Veltins Arena will be stepped up for the match, Breitenreiter backed the decision for Bundesliga action to continue in the wake of the terrorist attacks in Paris.
He said: "There are many countries all over the world where it is not possible to live in freedom. We should never give our freedom up.
"That's the reason why I'm convinced that it was the right decision that our game takes place.
"There is always the risk of an attack, so we have to trust our security authorities and especially we should trust security measures that the game can take place without any problem."
Key Opta stats:
- Schalke's last Bundesliga win over Bayern came in December 2010 (2-0). They haven't won any of the subsequent nine league meetings and have found the net in just four of those clashes. The Munich side have netted 25 times in that time frame.
- Pep Guardiola has faced Schalke four times in the league and has only recorded two victories. He failed to beat them 2014-15 (D2) and is yet to go three Bundesliga games without a win against a particular side.
- Bayern's tally of 34 points from 12 games is a new record. They have also set a new benchmark in terms terms of goal difference (+33) at this stage of the season.
- Robert Lewandowski has netted 14 league goals this term (a league high together with Pierre-Emerick Aubameyang). The last player to score as many goals after 12 games was Dortmund's Manfred Burgsmüller in 1980-81.
- Thomas Muller is just two goals shy of equalling his Bundesliga personal best return for a season (13, last achieved in 2014/15). The 11 he has already netted this term represents his best pre-winter break tally. He had never previously bagged more than nine before the turn of the year.
- Manuel Neuer has never lost to his former side in the Bundesliga (W6, D2). He stopped a penalty from Eric-Maxim Choupo-Moting in the most recent meeting (1-1 in February 2015).