Leader of the far-right Alternative for Germany (AfD) party has accused midfielder Mesut Özil, a practising Muslim, of promoting a political agenda by posting a picture of himself on social media on a pilgrimage to the holy city of Mecca last month.
In an interview with Die Welt am Sonntag newspaper, Frauke Petry also criticised Özil for not singing the national anthem, in the latest dig from the anti-immigrant party against ethnic minority members of the national soccer team.
Her comments came a week after the AfD's vice-chairman provoked outrage by saying people would not want black German soccer star Jerome Boateng as their neighbour.
"It's a shame that Mesut Özil, someone who so many children and young people identify with, does not sing the national anthem," Petry was quoted as saying in the paper.
Özil, a third-generation Turkish-German, has been held up as a prime example of successful integration into German society, and has been a stalwart of the national side since 2009.
There was no immediate response from the Arsenal star. The online version of Der Spiegel magazine said German players have no particular tradition of singing along to the national anthem before kick-off, and it is not unusual for them to remain silent, irrespective of their religion.
Asked about Özil's pilgrimage to Mecca, Petry accused him of hypocrisy and wanting to promote a political agenda.
"He doesn't live according to the rules of Sharia. At any rate, the women who he appears with in public, don't wear a veil," she added, in an apparent jab at his lifestyle.
The AfD maintains that Islam violates the constitution and wants a ban on minarets and face veils. The party has seen its support surge amid disenchantment with Chancellor Angela Merkel's open-door policy towards refugees fleeing conflicts and poverty in the Middle East and beyond. More than 1 million migrants arrived in Germany last year.
But the attacks on Germany's national team appear to have backfired on the party, with support for the AfD down 2 points to 12 percent, according to a poll published in Bild am Sonntag.
Germany's national team includes several other players of mixed ethnic background including defender Boateng, born in Berlin to a German mother and Ghanaian father, and Leroy Sane, whose father is former Senegalese international Souleyman Sane.
Meanwhile, another German right-wing populist politician has attacked Merkel as a "dictator" who is trying to "replace the German people" with migrants, a Sunday newspaper reported.
Alexander Gauland, of the AfD, told a rally outside Berlin that Merkel's liberal asylum policy was radically transforming the face of the country, the Frankfurter Allgemeine Sonntagszeitung said.
He called Merkel a "chancellor-dictator" to applause from the crowd and said Germany's mainstream parties were pursuing a policy of "human flooding," an "attempt to gradually replace the German people with a population coming from all parts of the earth."
Gauland, 75, is seen twice reading from a sign held by a member of the crowd: "Today we are tolerant and tomorrow foreign in our own country," a far-right slogan used by the neo-Nazi NPD party.
The three-year-old AfD has assumed an increasingly anti-immigrant and Islamophobic stance as Europe's biggest economy let in nearly 1.1 million asylum seekers last year. It is currently polling at about 15 percent nationwide after capturing seats in three state elections in March.
Analysts say it has tapped into angst over the migrant influx, which has slowed significantly in recent months, and bitter infighting in Merkel's ruling conservative bloc. Addressing the open dispute over asylum policy, Horst Seehofer, the head of the Christian Social Union, the Bavarian sister party to Merkel's Christian Democrats, pledged Sunday to try to bury the hatchet. "The chancellor and I have again created a basis of trust that we can build on," he told Bild am Sonntag newspaper.
Germany has recently witnessed anti-immigrant and Islamophobic demonstrations following the record influx of refugees. Several refugee centers were hit by violent protests and arson attacks. In the face of widespread hatred toward Muslims in German society, German authorities, including Chancellor Merkel and President Joachim Gauck, have condemned xenophobic attacks.
Anti-immigration ideology and xenophobia have become more visible in Germany, due to efforts by political parties like the far-right National Democratic Party (NPD) and AfD, as well as anti-Islam and anti-immigrant initiatives like PEGIDA, which have staged anti-immigrant rallies which have drawn thousands of people throughout Europe, as well as in Germany.