World No.5 Stefanos Tsitsipas on Monday became the highest profile victim at the US Open as the Greek crashed out of the first round a 6-0, 6-1, 3-6, 7-5 victim of Daniel Galan Riveros.

The unknown Colombian qualifier ranked 94 stunned the hampered seed eight days after Tsitsipas lost the Cincinnati final to Borna Coric.

Tsitsipas asked for the trainer after just one game in the first two sets, but the treatment session did little to stop the rot in a rout which took two and three -quarter hours.

Galan converted on seven of 15 break points.