Household names are not in abundant supply at this afternoon’s women’s semi-finals. Serena Williams we all know about, of course: one of the sisters who have dominated the Ladies’ Championship since the turn of the century.

But the rest? Two “ovas” and one “eva” are the others treading the turf of Centre Court in pursuit of glory. In the case of the “ovas”, it would be an historic moment indeed if either manages to push herself through to Saturday’s final, since Tsvetana Pironkova, the quarter-final conqueror of Serena’s sister Venus, is ranked 82nd in the world while Petra Kvitova, the only left-hander remaining, is 62nd.

No unseeded player has ever won the Venus Rosewater Dish, the symbol of supremacy in the world of women’s tennis. Nor has anyone unseeded even got as far as the final, so the ovas will be attempting the tennis equivalent of ascending Everest minus oxygen and crampons.

Not that this will deter these two women now they have got over their delighted astonishment at doing so brilliantly in the world’s premier tennis event.

But the form book has to say that Serena looks a certainty for her fourth victory here. The Williams family, with father Richard directing things, cheroot in hand, zero in on Wimbledon every summer as the peak of their year.

Serena has prepared for this fortnight by playing a mere five tournaments, including the Australian Open, which she won, and Roland Garros, where she exited in the quarter-finals. Not the slightest risk has been taken with injury; Wimbledon is what counts and the counting is pretty close to being over.

Perhaps not quite “ova” if Petra Kvitova has anything to do with the second of the semi-finals this afternoon. She knows well enough that Serena’s game is packed with dynamite, since in their only previous meeting, at the aforementioned Australian Open in January, she collected just three games in a second round match.

Serena is averaging just under 15 aces per match at the 2010 Championships, and is up to 73 already. She is winning 89% of her first serve points and is in, forgive the pun, serene cruise control. What can Kvitova (with 20 aces so far) do to counter such statistics? A resort to prayer might be the suggestion of some.

She could also take heart from the fact that the last left-hander to win the women’s crown here was also a Czech, who went by the name of Martina Navratilova.

As a practical 20-year-old from Fulnek in the Czech Republic, Petra will put that Australian Open demolition firmly behind her and think of the brighter moments she has enjoyed in the 2010 season, such as her semi-final place at the Memphis tournament, where she lost to Maria Sharapova.

Her one tournament victory came early in 2009 at Hobart, only her second year on the tour. She will be hoping that some of the success being enjoyed here by Tomas Berdych may rub off, since they train at the same club in Prostejov. Kvitova is the 10th unseeded player to make it into the Wimbledon women’s semi-finals since 2000.

As for her opponent today, Serena Williams has enough iron-clad achievements to construct a battleship. At the age of 28, she is striving for her fourth Wimbledon in the space of eight years and her 13th Grand Slam in all. She is back at world No.1 and certain to stay at the top, where she has reigned for 110 weeks altogether, after this tournament.

The Williams sisters are also currently world leaders in the doubles rankings and are keen to extend their Grand Slam holdings in this field of endeavour, so yesterday’s quarter-final loss to the Russian pair, Elena Vesnina and Vera Zvonareva (who Serena could meet in the singles final) will have come as a bit of a shock since they have won the Wimbledon doubles for the past two years.

Serena currently luxuriates as world No.1 at both singles and doubles, only the sixth woman in history to do so. If you are in search of a good pub trivia quiz question, the other five are Navratilova, Arantxa Sanchez-Vicario, Martina Hingis, Lindsay Davenport and Kim Clijsters.

In the other semi-final, Zvonareva (seeded 21st) takes on Pironkova, the destroyer of Venus, with the uncomfortable statistic that their only previous clash went the way of the Bulgarian. It happened in Zvonareva’s home town, Moscow, too, and by the embarrassing score of 6-0 6-2.

Summing up that drubbing, and forecasting what she must watch out for today, Zvonareva described Pironkova as an “all-over-the-court player”, adding: “Sometimes she can slice, sometimes she can hit the ball, sometimes she can play slow, sometimes she can play fast. You never know what to expect, so you lose your rhythm. Then maybe you start thinking too much.”

Vera’s proposed solution to this conundrum? Not to look on the other side of the net “and try to concentrate on myself”.

If she does reach the final, Zvonareva will probably crack the top 10. The sixth Russian woman semi-finalist in the Open era since 1968, she is hoping to follow Olga Morozova and Sharapova in becoming the third finalist from her country, in her 30th Grand Slam too.

As for Pironkova, with that convincing win over Vera to hold up as an incentive, she will take heart from being the first Bulgarian to get this far and the first at any Grand Slam in the Open era. Her reward will be a surge in the rankings to around 35, but if she can reach her first final the pay-off will be much, much more than that for the lady from Plovdiv.