Schalke have released midfielders Kevin-Prince Boateng and Sidney Sam as well as suspending Marco Hoger following their 2-0 defeat at Cologne on Sunday.
Schalke have been on a dismal run, winning just two of their last 12 Bundesliga games to drop out of contention for the Champions League spots, and they now face a battle simply to remain in the Europa League qualification places.
Sporting director Horst Heldt told Sky after Sunday's defeat that some players would not "survive the next training session" if they failed to show greater commitment, and the club issued a statement on Monday to confirm that action had been taken.
Boateng und Sam mit sofortiger Wirkung freigestellt. #S04 http://t.co/y4ICcco9gG pic.twitter.com/yOg0If0vCV
- FC Schalke 04 (@s04) May 11, 2015
"Schalke sporting director Horst Heldt announced there would be consequences after Sunday's defeat away to 1. FC Koln and the first action has been taken," a short statement on the official club website read on Monday. "Kevin-Prince Boateng and Sidney Sam have been released with immediate effect.
"Marco Hoger is suspended from training and first-team action up to and including Saturday May 16."
The loss leaves Schalke in sixth, only two points ahead of Borussia Dortmund and Werder Bremen, and Heldt had said regarding Sunday's loss: "We won't put up with a performance like that anymore.
"I don't know if all of [the players] will still be out there on the training pitch in the next 14 days. Many players have not delivered what they are a capable of. Sooner or later everyone will feel the consequences."
Boateng, who joined Schalke from AC Milan in the summer of 2013, was widely expected to leave the Royal Blues after two disappointing years at the Veltins Arena, which have seen him drop in the pecking order, particularly after his lacklustre performance in the 3-0 defeat at Borussia Dortmund in late February.
The midfielder had returned to the starting lineup for the game at Cologne after he scored a last-minute winner in the 3-2 victory over bottom club Stuttgart last week, but another poor display has brought an early end to his time in Gelsenkirchen.
The 28-year-old, who has not featured for the Ghana national team since being sent home from last summer's World Cup, has been linked with a move to China in recent weeks.
Sidney Sam, meanwhile, had arrived at the Veltins Arena on a free transfer from Bayer Leverkusen only last summer but has also left the club after a highly disappointing season.
The 27-year-old former Germany international has featured in just 11 Bundesliga games, last playing for the club in the 0-0 draw with strugglers Freiburg in mid-April.
Hoger, though, could return for the Royal Blues' last league game at Hamburg in two weeks.
The 25-year-old midfielder, who joined Schalke in 2011, had returned to the team on Sunday following a minor injury and has played in 25 Bundesliga games this season.
Regarding Hoger, who is under contract until 2016, Heldt had said: "We question his loyalty. But we have granted him a week to think about it, and we will talk next Sunday to discuss whether it makes sense to continue the partnership beyond the summer."