Rotterdam, Netherlands: Rising Greek star Stefanos Tsitsipas said he "lost to himself" after suffering a shock defeat at the ATP event in Rotterdam by Bosnian Damir Dzumhur on Wednesday.
The 20-year-old, who dumped out Roger Federer en route to the Australian Open semi-finals last month, saved two match points late in the third set but still slumped to a 6-4, 1-6, 7-5 loss.
It was Dzumhur's first win since October after a run of four straight defeats, and Tsitsipas was left frustrated by an erratic display.
"I lost to myself, not to him," said the world number 12.
"He fools you, waits for you to make mistakes. He stands eight metres behind the baseline and plays with your strengths. He played nothing crazy or special, but you don't get any rhythm with him.
"The momentum was on my side but he kept putting the ball into the court and running."
Tsitsipas was seeded third at the Ahoy Arena, but has now lost three of his last four matches after his Melbourne last-four thrashing by Rafael Nadal with a quarter-final exit at the hands of Gael Monfils in Sofia last week.