The Red Devils have been linked with a surprise move for the Croatia international in recent weeks as Louis van Gaal looks to improve his attacking options at Old Trafford.
Mandzukic, who won the Champions League winner in 2013, moved to the Spanish capital last summer after he was deemed surplus to requirements by Bayern Munich manager Pep Guardiola.
But in spite of interest from the Premier League, the Croatian’s agent Ivan Cvjetkovic tipped the giant striker to see out his Atletico contract, which runs until 2019.
“Mario was unhappy recently because he had stopped scoring and that affected him but that was also down to Atletico Madrid,” Cvjetkovic told Tportal.
“In spite of this, this Atletico side still qualified for the Champions League and won the Supercopa de Espana, so there’s no reason to think he’s totally unsatisfied.
“When you go to a new league, the first year is always one of adaptation. Anyway, the fans immediately took to him. Mario adapted to both the club and the city.
“I don’t see any reason why he should not fulfil his contact. Of course, we know well that in football things are always changing and you never know what can happen.
“However, I don’t think it’s necessary to speculate about the future right now.”
Mandzukic scored 12 goals and made five assists in 29 La Liga games for Los Rojiblancos in his first season at the club.
United striker Robin van Persie is being linked with a move away from Old Trafford despite scoring 10 times in 25 Premier League starts.
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