British number two Cameron Norrie lost 6-2 6-2 to Spain's Albert Ramos Vinolas in the first round of the Barcelona Open on Tuesday.
The 23-year-old, who climbed to 45th in the latest ATP world rankings, lost serve at the start of both sets before losing the final three games.
Vinolas, 31, is ranked 38 places below the Briton and will now face Russia's Daniil Medvedev in the last 32.
Norrie is set to play at next month's French Open at Roland Garros.
The loss comes less than a week after Norrie exited the Monte Carlo Masters in the round of 16 to Italian Lorenzo Sonego, ranked 40 places below him.