Australian second seed Bernard Tomic served up 14 aces but was still knocked out of the 's-Hertogenbosch grass court tournament by two-time champion Nicolas Mahut on Friday.
Mahut, the 2013 and 2015 champion at the Wimbledon warm-up event, won 6-7(5/7), 6-4, 6-2 to set up a semi-final clash against America's Sam Querrey.
Victory for Mahut over Tomic was also revenge for a loss he suffered in their only other meeting in Brisbane in January.
“It is really difficult to play against Bernard on grass, so I am happy with the way I was able to come back after the first set,” Mahut said.
“I served much better and the early break in the second set gave me a lot of confidence.”
Luxembourg's Gilles Muller fired 17 aces in a 4-6, 6-4, 7-6 (7/5) upset of top-seeded Spaniard David Ferrer of Spain.
The big left-hander saved four of five break points and secured victory on his third match point.
He will face Ivo Karlovic in the semi-finals after the Croatian third seed beat France's Adrian Mannarino 6-3, 6-4.
Fifth seed Querrey had earlier defeated compatriot Stefan Kozlov 6-3, 6-0.
In the women's event, top seed Belinda Bencic edged Swiss teammate Viktorija Golubic 7-6 (8/6), 7-6 (7/2). – AFP