After a wildly unpredictable women"s singles at the French Open, four Grand Slam semi-final debutants will line up on Thursday with a golden opportunity knocking. Not since the 1978 Australian Open have a quartet of players reached the semis of a women"s Grand Slam for the first time. Chris O"Neil, ranked 111 in the world, won the title on that occasion although it was a relatively weak field with few of the top players even bothering to play the event. The same cannot be said this year and whoever out of Russia"s Anastasia Pavlyuchenkova, Slovenia"s Tamara Zidansek, Czech Barbora Krejcikova and Greek player Maria Sakkari holds the trophy aloft on Saturday will have truly earned it. First up on Thursday on Court Philippe Chatrier is 31st seed Pavlyuchenkova against 85th-ranked Zidansek, the first Slovenian player to reach the semi-finals of a Grand Slam. Unseeded Krejcikova then takes on 17th seed Sakkari who, in becoming the first Greek woman to reach a Grand Slam semi-final, enjoyed back-to-back wins over last year"s runner-up Sofia Kenin and on Wednesday reigning champion Iga Swiatek. After a fortnight of upsets at Roland Garros, no one in their right mind would wager their mortgage on who might be the last women standing. Pavlyuchenkova, the oldest of the four semi-finalists at 29, has been knocking on the door in Grand Slams since she reached the French Open quarter-finals in 2011. She lost that one and the next five Grand Slam quarter-finals she contested before finally breaking through that glass ceiling by outlasting Kazakhstan"s Elena Rybakina in a marathon three-set battle on Tuesday. "I think I have always had the game. I have always played good. It"s just I mentally wasn"t there. I wasn"t fit enough and mentally maybe not strong enough," the Russian said. COURT CRAFT Zidansek had never won a main draw match at the French Open until she ousted former U.S. Open champion Bianca Andreescu in the first round -- a result she said fuelled her with belief. She showed great court craft to come through a topsy-turvy quarter-final against hard-hitting Spaniard Paula Badosa and will hope to mix it up against Pavlyuchenkova. "I need to be able to confuse her with my game, to run out a lot of balls, put a lot of balls back," the former competitive snowboarder said looking ahead to the semis. Sakkari"s straight sets win over Swiatek on Wednesday means that for the first time a Greek player has reached the semi-finals of the women"s and men"s singles at the same Slam after Stefanos Tsitsipas beat Daniil Medvedev on Tuesday. On paper she is now the favourite but she lost to Krejcikova in Dubai in March and knows that while the title is tantalisingly in view, it remains a long way away. "I am the highest-ranked player but the rest of the girls are playing extremely well. I think the draw has changed so much so it doesn"t really matter who was the highest ranked in this tournament," she said. Krejcikova, known more as a doubles specialist, stretched her winning run to a career-best 10 matches when she stopped the run of American teenager Coco Gauff on Wednesday and is hoping to become the first Czech player to win the women"s singles in Paris since Hana Mandlikova in 1981. If she does she says it will be a tribute to the late Jana Novotna who helped her along the road to professional tennis. "I feel like she kind of always knew that I can play this high level, that I can play matches like this," she said after beating Gauff. "It"s just sad that it didn"t happen earlier."