Pascal Ackermann says Bora-Hansgrohe team boss Ralph Denk did not keep his word after he missed out on the team's Tour de France squad.
The German was expected to line up alongside Peter Sagan as one of two sprinters for the Tour.
However, with Ackermann failing to win a race so far this season and Wilco Kelderman in contention for the GC, he has not been selected to race.
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Emanuel Buchman is to provide support and potentially cover for Kelderman at the Tour which gets underway live on Eurosport from June 26.
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Ackermann is not pleased with the decision and feels he has been on the receiving end of a broken promise.
"I'm more than disappointed, I have to say. Ralph was always a man who kept his word. But this time he definitely didn't do it," Ackerman told German website Radsport News.
"It was said that I would be doing the Tour for three years, and it was always the case that I shouldn't worry about it.
Without this promise, I would not have signed the contract back then. You have to see that too. That's why I am extremely disappointed.
"Of course there was no victory yet but that is no reason for me not being allowed to participate if the form is right. And it was right.
"If I knew that I'm not in shape, I would understand. But everyone knows, and you can see from the data, that the reason (for non-selection) is not my form.
"I can't understand the reason. And the team knows that too. That's why I'm so disappointed."
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