Arne Friedrich has denied the decision to cancel his contract at Wolfsburg was based on stress or mental exhaustion.
The injury-plagued 82-time Germany international was in September granted his wish and his former club agreed to terminate the remaining year-and-a-half of his deal.
Rumours have suggested the 32-year-old was suffering from stress after playing just 15 Bundesliga matches since joining Wolfsburg in the summer of 2010.
Schalke manager Ralf Rangnick earlier this season stepped down due to mental exhaustion, but Friedrich insists he is not suffering from a similar illness.
He told his official website: "Dear Supporters, at first I want to wish Ralf Rangnick all the best and a swift recovery from his illness.
"I want to express my deepest respect for his decision (to leave Schalke). It certainly was not an easy decision to make.
"I am aware that in recent days there were also rumours I have cancelled my contract with Wolfsburg due to this illness.
"This is what I want to deny. I feel well. I wish Wolfsburg all the best for the season and the best success in the future."