Pictures from Bayern’s training ground on Tuesday showed Wagner in tears while being consoled by teammates such as super star Robert Lewandowski.
Bild reported that the squad gave the crestfallen 30-year-old a round of applause, and that Bayern manager Jupp Heynckes addressed the issue with the group.
The German daily newspaper claims that the veteran manager said that he could not understand the decision, and would have selected Wagner had he been Germany coach.
Speaking after announcing his preliminary squad earlier on Tuesday, Germany boss Joachim Löwsaid that it was a tough call to select Freiburg front man Nils Petersen ahead of Wagner, but one that did not reflect badly on the Bayern player.
“My job as national manager is unfortunately also to shatter dreams and make hard decisions,” the 58-year-old said.
“It is never against a player, but always in the interests of the team.”
And now after his omission from Germany’s preliminary squad, Sandro Wagner had his say:
“I would be lying if I said I’m not disappointed. Playing in the World Cup would have been great. Of course, I can’t take this seriously, but as I have often said in the past, there are more important things in life than football.”
“It’s clear that my open, honest and straightforward manner doesn’t fit in with the coaching team. I wish the lads all the best in Russia and hope that they return as world champions.”
“I am hereby retiring from the national team with immediate effect,” Wagner told Bild.
Wagner made his debut for Germany in June, scoring five goals in eight games. He was part of the side that won the Confederations Cup last summer in Russia.