Swiss wildcard Stan Wawrinka has booked a quarter-final spot at the ATP Tour event in Rotterdam with a straight-sets win over Canadian fourth seed Milos Raonic.
Wawrinka, seeking his first title since he had knee surgery in 2017, overcame the big-serving Raonic 6-4 7-6 (7-4).
Three-time grand slam winner Wawrinka's reward is a showdown with another Canadian after 10th seed Denis Shapovalov defeated Tomas Berdych 6-4 6-3.
"Tonight was a really good level, that is for sure," Wawrinka told reporters.
"It is one of the best matches I have played in many months now.
"So far I have (played) two great matches (in Rotterdam), tonight was a great performance."
Wawrinka was delighted with his form as he had been beaten by Raonic in their past three meetings.
"I was feeling great physically, so that is how I can start to engage the rally," he said.
"I was returning better because I reacted better and that gave me way more chances to be aggressive."
Frenchman Gael Monfils is another played into the last eight courtesy of his 4-6 6-1 6-3 defeat of Andreas Seppi.
Earlier on Wednesday, Damir Dzumhur notched his first victory of 2019 when he outwitted third-seeded Greek Stefanos Tsitsipas 6-4 1-6 7-5 in an opening-round match.
Elsewhere in the first round, Russian fifth seed Daniil Medvedev beat Jeremy Chardy 7-6 (7-2) 6-2, Jo-Wilfried Tsonga was a 6-1 6-4 winner against Thomas Fabbiano and Marton Fucsovics sank Martin Klizan 7-6 (7-4) 6-4.