The Estonian finished 25.6 seconds ahead of Citroen's Finnish driver Esapekka Lappi with Toyota's Finn Jari-Matti Latvala third.
Tanak also won the final Power Stage for an extra five points.
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After nine of 14 rounds, Tanak has 180 points to reigning champion Ogier's 158 with Hyundai's Belgian Thierry Neuville on 155.
More to follow.
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