With six league matches remaining, Bayern Munich's title credentials will face a stern examination on Saturday at Mainz, one of the Bundesliga's form sides.
Bayern's Champions League elimination at the hands of Manchester City on Wednesday, along with their German Cup exit earlier in April, means only one chance of silverware remains for the trophy-hungry club.
Bayern lead the Bundesliga but Borussia Dortmund are just two points behind.
Bayern manager Thomas Tuchel said the Mainz clash would be a test after Wednesday's 1-1 home draw with City completed a 4-1 elimination on aggregate.
"On Saturday, we want to be ready for the next fight, which is definitely a character test."
Tuchel said Bayern could take "plenty of positives" from "matching it with the best team in Europe, the most in-form team in Europe". But he acknowledged that the contrasting 1-1 draws with Manchester City on Wednesday and with lowly Hoffenheim in the Bundesliga the previous weekend, suggest his team is inconsistent.
"Today (Wednesday) we were really on a high level. On Saturday, we were not.
"We need to be on a high level on Saturday against Mainz."
Of immediate concern is Bayern's misfiring attack.
The forwards, who include Sadio Mane, Serge Gnabry, Leroy Sane, Kingsley Coman, Thomas Mueller and Jamal Musiala, have failed to score for five matches.
In that period, four goals have come from defenders and one from a penalty converted by defensive midfielder Joshua Kimmich.
Tuchel cut his coaching teeth at Mainz from 2009 to 2014, a club known for making canny choices to overcome budget limitations.
Mainz manager Bo Svensson, who played for five years under Tuchel, said on Thursday the Bayern manager "was one reason why I took the path to become a coach."
Svensson said Tuchel helped him "find my identity and what I want to stand for".
Unbeaten in nine matches, Mainz have also won the last two times Bayern have visited in the league.
Dortmund host Eintracht Frankfurt on Saturday evening.
After conceding three goals in the final 12 minutes for a disappointing draw at Stuttgart last week, Dortmund will welcome back central defenders Nico Schlotterbeck and Niklas Suele from injury.
The Germany centre-back pairing were crucial during the side's 10-match winning streak to start 2023, with Dortmund in particular missing the steel and desperation of Schlotterbeck.
One to watch: Ludovic Ajorque (Mainz)
Towering Mainz striker Ludovic Ajorque has been a big reason for the side's resurgence since arriving from Ligue 1 side Strasbourg for six million euros in January.
Having played his entire career in France, Ajorque, 29, has scored five goals in 12 matches for Mainz – all in the past seven games.
It's an excellent return for the forward, who had scored just once in 13 Ligue 1 appearances this season, and has helped push overachieving Mainz to within reach of the European placings.
Key stats
0/7 - Frankfurt manager Oliver Glasner has lost each of his seven games against Dortmund, with both his current club and former side Wolfsburg.
0/7 - Frankfurt are winless in seven in the league (four draws, three losses), a run stretching back to mid-February.
23 from 13 - Mainz have picked up 23 points in 13 league matches since the World Cup. Only Dortmund (32), Leverkusen (26) and Bayern (25) have more.
Fixtures (all times 1330 GMT unless otherwise stated)
Friday
Augsburg v Stuttgart (1830 GMT)
Saturday
Hoffenheim v Cologne
Bochum v Wolfsburg
Hertha Berlin v Werder Bremen
Mainz v Bayern Munich
Borussia Dortmund v Eintracht Frankfurt (1630 GMT)
Sunday
Freiburg v Schalke
Bayer Leverkusen v RB Leipzig (1530 GMT)
Borussia Moenchengladbach v Union Berlin (1730 GMT)