Court in a trap? Wobbly Serena faces test against wily Strycova

American superstar Serena Williams is tantalisingly close to equalling Margaret Court's record haul of 24 Grand Slam titles but it's far from a certainty given her shaky displays so far at Wimbledon.

The 37-year-old seven-time champion had to draw on all her strength -- physical and mental -- to get past unseeded compatriot Alison Riske in the last eight and faces another grass court loving opponent in Barbora Strycova in Thursday's semi-finals.

The 33-year-old Czech veteran -- the oldest player to play in a woman's Wimbledon semi-final for the first time -- has played some wonderful tennis and says she will step onto Centre Court "without any fear".

The other semi-final pits two seeds against each other, seventh seed and former world number one Simona Halep against eighth seeded Ukrainian Elina Svitolina.

It says a lot about the turbulence of women's tennis that Williams is making her 12th semi-final appearance while of the other three only Halep has gone this far before, and that was back in 2014.

Williams is the colossus that still bestrides women's tennis, but there are chinks in her armour as have been exposed both at Wimbledon and in her last two Grand Slam finals.

Outplayed by Angelique Kerber in last year's Wimbledon final and then a spectacular meltdown in the US Open defeat by Naomi Osaka gives Strycova genuine hope of an upset.

Not that the diminutive Czech will require any as her bubbly character oozes optimism and her form guide is as good as any of the semi-finalists having ousted four seeds on her way to the semi-final.

Williams's clay court campaign was affected by a knee injury but has accrued invaluable extra game time by playing the mixed doubles with another former world number one, Andy Murray.

"This is the first time since Australia (she reached the quarter-finals of the Australian Open) that I actually felt, like, good," said Williams.

"It's been a really, really long year for me already, and hard year, because I'm usually not typically injured.

"I don't know where I am. I do know I feel good." However, she has still looked vulnerable and Strycova's speed round the court and array of shots will pay dividends if she reproduces the leaden-footed performance she put up against Riske.

- 'She never quit' -
=====================
"You have no idea how hard she worked to come back to that level, and she came back for that, so it will probably mean a lot if she makes it."
"I don't have fear,"
"I have really at this point nothing to lose."