Reports in the Spanish Press claim that Real Madrid have been put on alert after Mario Mandzukic admitted he wants to leave Bayern Munich.
The Croatia international has been a mainstay for the Bavarian side during their wildly successful two years.
But with Robert Lewandowski coming in from Borussia Dortmund, the goalscorer has conceded that he may have to depart Allianz Arena.
“At Bayern it was fantastic. It's a fantastic club. Indeed, until recently I didn't even think about leaving, and especially that it would happen now," he told Sportske Novosti.
“Let's be honest, the style Guardiola wants at Bayern doesn't suit me.
“In the first leg against Real Madrid [in the Champions League], I definitely understood, no matter how much I try, I can't get the best out of myself with this style.
“When it's like that, I don't feel good and it's best for everyone that we part.
“Thanks to the club who offered a contract extension, thanks to Guardiola, who is a great Coach, and I wish everyone all the best for the future.
“Bayern and their fans will always be the most beautiful and most emotional story of my career. The time has come for new challenges.”
As such, Marca insist that Los Blancos are considering the possibility of signing the former Wolfsburg man – but only if they fail in their approach for Luis Suarez.
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