Wild card Tatsuma Ito shocked top seed Stan Wawrinka of Switzerland 7-5, 6-2 in their first-round match at the Rakuten Japan Open on Tuesday afternoon.
With the roof open at a sun-drenched Ariake Colosseum, Ito took the initiative from the outset and never looked back, prevailing before a partisan crowd in just 1 hour and 19 minutes.
Wawrinka, ranked No. 4 in the world, was sluggish throughout the contest while committing a high number of unforced errors. He put up a bit of resistance in the opening set, but could not muster much of an effort in the second on the way to defeat.