Werder Bremen on Tuesday suspended Naby Keita "until the end of the season" and handed the midfielder "a substantial fine" after he refused to play against Bayer Leverkusen on Sunday.
Former Liverpool midfielder Keita was told before Sunday's trip to Leverkusen he would not be in the starting XI. The 28-year-old refused to board the team bus and instead went home.
"We won't tolerate Naby's behaviour," Bremen sporting director Clemens Fritz said in a statement, saying the club had "no alternative."
"He let his team down in a time of difficulty surrounding our recent run of form and squad availability and put his own interests above those of the team. We can't allow that."