Former world number one Andy Murray reached his first semi-final since the 2017 French Open with a battling three-set win over Romania's Marius Copil in Antwerp.
The 32-year-old British star, steadily rebuilding his career after major hip surgery earlier this year, defeated qualifier Copil 6-3, 6-7 (7/9), 6-4.
"I feel OK, it's more how you pull up the following day," said Murray, who is two wins away from a first title since Dubai in March 2017.
"The good thing about the indoor matches is that the points are fairly short so it doesn't take as much out of you as on some of the slower courts outside."