Victory for world No 1 Angelique Kerber helped Dominika Cibulkova reach the semi-finals of the WTA Finals on Thursday. Kerber, who had already advanced from the Red Group, beat Madison Keys 6-3 6-3 at the Singapore Indoor Stadium to finish 3-0 in the round robin and eliminate her American opponent.Cibulkova beat Simona Halep 6-3 7-6 (7-5) earlier in the day, giving her a 1-2 record. After losing her opening round robin matches to Kerber and Keys, the Slovak needed a straight-sets win to have any chance of advancing and she managed to keep her side of the bargain in a display full of determination.Her victory ensured the unbeaten Kerber qualified for the semi-finals without hitting a ball and the top-ranked German returned the favour in the late match by beating Keys in straight sets to take Cibulkova through with her.Today I wasnt thinking about that I already was in the semis, Kerber said. It was important to go out to win the match and win all three matches.Now Im going to the semis with three really good matches which gives me a lot of confidence. Dominika Cibulkova beat Simona Halep to advance Halep had her left knee heavily strapped and was clearly in some discomfort but, knowing she needed a set to keep her hopes alive, she battled manfully to force a decider.However, it was seventh seed Cibulkova who won the second-set tie-break and the match.This win is really, really big for me, said the 27-year-old. I feel relieved. Im really, really happy about my win, about the way I played and the way I handled the situation and the pressure.It seems like Im playing my best tennis under the biggest pressure. To beat Simona in two sets - knowing that if I want to go further in the tournament, I have to beat her in two sets. That made me even stronger in the second set. Watch NOW TV Watch Sky Sports for just £6.99. No contract. Australian Open and US Open champion Kerber will be playing in the semi-finals of the season-ending tournament for the first time after failing to advance in three previous attempts.In the semi-finals, Cibulkova will face White Group winner Svetlana Kuznetsova while Kerber will take on the winner of Fridays clash between Agnieszka Radwanska and Karolina Pliskova with Garbine Muguruza already eliminated.Watch the Erste Bank Open live on Sky Sports on Friday from noon on Sky Sports 3 HD.You can watch Premier League and EFL Cup football, plus Englands tour of Bangladesh and the Mexican Grand Prix on Sky Sports. Upgrade now and enjoy six months at half price! Also See: WTA Schedule Radwanska bounces back at Finals Kuznetzova edges Pliskova Tennis on Sky RIO DE JANEIRO -- Theres no better finisher in womens rugby sevens than Portia Woodman.Finishing tries is the forte of the woman called `Porsh, and shes scored in all four of her matches at the Rio de Janeiro Olympics, including the 5-0 match-winner against the United States in the quarterfinals on Sunday to propel New Zealand into the medal rounds.Yet, Woodmans speed wasnt the highlight on day two of the womens competition, but rather the powerful defense she and her teammates produced.With the stakes higher, she simply burned every opponent who came near her.In the morning Pool B decider against France, the first serious test of world champion New Zealand, the 5-foot-7 (1.69-meter) winger flattened forward Elodie Guiglion, then bowled over two defenders in scoring a first-half try, her fifth of the tournament. In the second half, Woodman put Jessy Tremouliere on her back, and set up Kayla McAlister for the last try in the 26-7 win.Against the Americans, Woodman smashed over Lauren Doyle to force a turnover. The quarterfinal was distinguished by defense, especially when New Zealand led by five and played a woman down for two minutes with 3 1/2 minutes to go. They held on.Of her big hits, Woodman said, I was just vibing off all the girls. Were pretty much all connected, and when someones firing, were all firing.She said they trained often to deal with yellow cards, and knew what to do when Tyla Nathan-Wong was sin-binned for a late tackle.All we could think was coach saying, `Youve got two minutes, six players, tough it out, she said. Its tougher to do mentally than physically because you aalways know youre one down, and theres so much more space there.dddddddddddd Its crazy how much the difference one person makes.Her try originated from a scrum, McAlister drew two defenders on the halfway line, and Woodman out-ran them on the outside to the posts.Shes a superwoman, she said of McAlister. She brings in two players and leaves me out there wide, so its an easy job for me. All my tries have come from her.It seems so. They have become one of the great partnerships in rugby. Both were netballers who were among more than 1,100 who answered a `Go4Gold initiative in 2012 to put together a New Zealand womens sevens team for these Olympics. They stood out immediately, developed a seemingly telepathic understanding, and were key to New Zealand winning the first three womens world series, and the Sevens World Cup.McAlister, whose brother Luke was an All Black, was the first world womens sevens player of the year in 2013, and Woodman was honored in 2015.Woodman is the all-time leading try-scorer in womens world series history, with 119 over four seasons. Shes been top try-scorer in the series three times, and last year became only the fifth player -- man or woman -- to score more than 50 tries (52) in a single series.Her father, Kawhena, and uncle Fred were All Blacks in the 1980s, and she said shes followed her dads advice on the field since she was aged 7, and beating boys.My Dad told me way back when I started, she said, just get the ball and run like heck. ' ' '