Bayern are keen to add another winger to their squad and have previously been linked with Borussia Monchengladbach star Marco Reus.
Nevertheless, they also see the 24-year-old Mertens as a potential candidate. A Bayern delegation visited last Saturday's Eredivisie match between De Graafschap and PSV to see the attacker in action.
Mertens joined PSV from Utrecht in the summer transfer window and has since developed into one of the stars of the Netherlands' top tier. He has so far scored 11 goals in 13 Eredivisie appearances and set up seven more.
The former AGOVV star has a contract with PSV until the summer of 2016 and an offer well over €10 million could be needed to lure him away from the Eindhoven giants.
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