Kim Clijsters reached the semi-finals of the s-Hertogenbosch grasscourt tournament on Thursday, defeating Italy's Francesca Schiavone 6-3, 7-6 (9/7).
Former world number one Clijsters, who before this week hadn't played since March because of a right hip injury, was the champion in this pre-Wimbledon event in 2003.
And she showed on Thursday that she could be a genuine threat at this year's Wimbledon which starts on Monday.
"It was a very intense match. Schiavone is a player who keeps fighting and has all sorts of different strokes. It is very important to stay focused," said Clijsters, who will face Poland's Urszula Radwanska for a place in the final.
"I am very happy that I can play an additional match before I go to Wimbledon," added the 28-year-old Belgian who will retire after the US Open.
In the men's tournament, world number six David Ferrer dropped just three points on serve in a 6-0, 6-1 rout of Dutch wild card Igor Sijsling.
"Sometimes you find good feelings and sometimes it works," said Ferrer. "Today I was very good throughout the match, attacking well with my first serve, and maybe he was a little bit nervous."
The top-seeded Ferrer is bidding to win this grasscourt tournament for the second time after victory on his debut in 2008.
Ferrer goes onto face France's Benoit Paire, who fired 15 aces as he defeated Japan's Tatsuma Ito 6-3, 7-5 in 72 minutes.
German qualifier Philipp Petzschner struck 14 aces and broke serve twice as he overcame Frenchman Edouard Roger-Vasselin 6-4, 7-6 (8/6) in one hour and 35 minutes.
He will face Belgium's Xavier Malisse, who battled past Gilles Muller of Luxembourg 6-3, 4-6, 6-1 in 86 minutes.