Ex-England boss Steve McClaren managed Arnautovic at FC Twente and tells colleagues the 24-year-old is completely mad, says the Sunday Mirror.
Arnautovic has vowed to turn over a new leaf after the birth of his baby daughter, and having ended his 18-month international exile.
"I must keep myself under control," he said. "I have a big responsibility as a father. That helps me to be more sensible. It's better I keep my mouth shut. Let my feet do the talking."
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