Dortmund boss Sahin warns of 'unbearable' fixture list

Sahin announced centre-back Niklas Suele would miss "several months" with an ankle injury, the latest addition to Dortmund's overcrowded sick bay. "The strain is almost unbearable, especially for international players. I don't know when they are supposed to have a break," said Sahin.

In addition to Suele, last season's Champions League finalists are missing midfielders Julian Brandt and Karim Adeyemi, forward Maximilian Beier along with defender Waldemar Anton, all of who have played for Germany in recent seasons.

The 36-year-old, who played for Real Madrid and Liverpool as well as Dortmund before becoming a coach, said travel and the style of modern football were also to blame. "They travel from A to B, from B to C, and when they get back I'm bombarding them with information about their next opponents," he said.

"On top of that, the game has changed completely in recent years... 10 to 15 years ago, the game was different, with fewer sprints and a lot less running. Nowadays you have to push yourself to the limit in every game."

Several other players and coaches have hit out at the fixture schedule, with some floating the idea of industrial action. Spain and Manchester City midfielder Rodri said players were considering striking earlier in the year, weeks before he went down with a season-ending ACL tear.

Sahin pointed out that many of Europe's biggest clubs, including Bayern, Barcelona and Real "had a lot of injuries this year".

"Neither Pep (Guardiola) nor Jurgen Klopp were able to change that after speaking at press conferences, so if Nuri Sahin says something, likely, FIFA will not say 'we will change it'," he added. "But the workload is simply too high."

Dortmund and Barcelona are level on 12 points, with the Spanish side sitting in third, one spot ahead of Wednesday's hosts, on goal difference.