A coalition of Borussia Dortmund fan groups, who stand on the iconic south terrace, say they plan to boycott their club's first Bundesliga game held on a Monday.
For the first time, the German Football League (DFL) is experimenting with five Monday night games this season in the Bundesliga.
The first kicks-off at 2030 local time (1930 GMT) on February 19 when Eintracht Frankfurt host RB Leipzig.
Dortmund are at home to Augsburg in the second planned Monday match on February 26 and Borussia fans are opposing the initiative.
"With a heavy heart, but out of conviction, we have decided to stay away from the game against Augsburg and not use our tickets on that day," said the coalition "Suedtribune (south stand) Dortmund" in a statement released on Friday.
"This decision is in no way directed against the team, but we can not -- and will not -- accept Bundesliga matches on Mondays!"
German fans, always vocal about changes to kick-off times.
Bundesliga match days are currently restricted to Friday, Saturday and Sunday kick-offs with the occasional round of mid-week matches.
Dortmund fans hope to force German Football League (DFL) bosses into a rethink if the iconic south terrace -- nicknamed 'the Yellow Wall' which holds around 24,000 -- is empty during games.
"For the Bundesliga, which likes to present itself with its atmospheric terraces and sold-out stadiums, Monday games are a declaration of bankruptcy," the statement added.
"When matches take place on dates when nobody actually has time to go to the stadium, that reveals the dreadful indifference to the social importance of football and the fans who make the sport what it is."