British number one Katie Boulter was knocked out of the US Open second round in a "horrendous" straight-set defeat by Spain's Jessica Bouzas Maneiro.
Boulter, the 31st seed, started strongly in the opening set, breaking first before Bouzas Maneiro found her footing.
The world number 74 stormed into the lead in the second set and held off a late surge to close out a 7-5 7-5 victory.
Boulter was heard saying "everything was horrendous" to her team at the side of the court.
"A really tricky match for me. Today I was a little too passive and I didn't quite play the way I wanted to play," Boulter told BBC Radio 5 Live.