SINGAPORE: Dominika Cibulkova kept her hopes of reaching the last four of the WTA Finals alive with a gritty 6-3 7-6(5) Red Group victory over Simona Halep at the Singapore Indoor Stadium on Thursday. After losing her opening round robin matches to Angelique Kerber and Madison 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 Cibulkova will be hoping the German can return the favour in the late match by beating Keys in straight sets to take the Slovak through with her. The American, however, needs to take just one set off world number one Kerber to advance while Halep, the losing finalist at the elite eight-woman event in 2014, was eliminated following the loss to Cibulkova. Cibulkova came out all guns blazing, looking far more composed and urgent than her opponent, harrying Halep on every point and breaking to love at the first opportunity as she raced to a 3-0 lead in less than 10 minutes. Halep, whose left knee was heavily taped, was struggling to get a foothold in the contest but after halting Cibulkova’s winning streak at 13 points, the Romanian eked out a hold to finally get on the scoreboard in the fourth game. The Slovak continued to look focused and determined to move 5-2 ahead and although the Romanian enjoyed her easiest hold of the match in the eighth game, Cibulkova sealed the opening set with a big serve down the middle that Halep sent long. The world number eight started the second set as she had the first, utilising her devastating forehand to break in the opening game as she pushed for the straight sets triumph she needed to stay in the tournament. Halep knew she needed to stem the flow quickly to avoid being blown away and the Romanian dug deep to forge her first two break points of the match and seized the second of them to level up the second set at 1-1. Cibulkova was still on the front foot and calling the shots but after breaking her opponent twice in a row towards the end of the set, Halep came storming back and tensions mounted as the set moved inevitably to a tiebreak. Still playing the aggressor, the Slovak edged ahead after the change of ends before she polished off a brilliant victory when Halep sent a backhand wide on the first match point.