British number one Kyle Edmund crashed out of the Estoril Open yesterday after losing in the quarter-finals to Joao Sousa.
Edmund, ranked 23rd in the world, was beaten 6-3 1-6 6-0 by the Portuguese world number 68 in 88 minutes.
The two will meet again on Saturday, however, when Edmund and Cameron Norrie play Sousa and Argentina's Leonardo Mayer in the men's doubles semi-finals.
Defending champ Alexander Zverev advanced to the semi-finals of the Munich Open by beating Jan-Lennard Struff 6-3 6-2.
The top-seeded Zverev will next face fourth-seeded Chung Hyeon, who defeated 2014 champion Martin Klizan 6-3 6-4.
Petra Kvitova, meanwhile, moved a step closer to winning her second title of the year when she beat China's Zhang Shuai 7-6(6) 6-0 in the semi-finals of the Prague Open.
The Czech faces seventh seed Romanian, Mihaela Buzarnescu in today's final.