Second-ranked defending champion Coco Gauff crashed out in her opening match at the Cincinnati Open, falling to Yulia Putintseva 6-4, 2-6, 6-4 on Thursday.

The second-round shock to America's Paris Olympic flag bearer stunned a partisan crowd in the U.S. heartland in the final major tuneup for the U.S. Open, where Gauff is the defending champion.

Kazakh spoiler Putintseva, ranked 34th, has made a recent habit of upsets, knocking off world No. 1 Iga Swiatek in the third round of Wimbledon barely a month ago.