Day four in the Singapore finals witnessed the White Group play out its next rostered round robin matches. Both sets of matches were interesting and for different reasons. Here’s a quick recap of the day’s action:  Svetlana Kuznetsova (RUS) def.
 Karolina Pliskova (CZE) 3-6, 6-2, 7-6 (6) The Russian stumbled, righted herself, tottered again before finally getting it correctly in her clash against the Czech. It was Pliskova, who took the lead, as she raced to a 4-1 lead over the seemingly tired Kuznetsova.
But two games later, Kuznetsova got the break back only to give it back again as Pliskova, broke for the second time in the set to lead 5-3. When she served for the set in the ninth game, she finished it off without any fuss to go up 6-3 in the match.
The second set began in pretty much the same fashion, with Pliskova breaking Kuznetsova in the opening game itself. This time though, Kuznetsova pounced back, first securing the retaliatory break and following it up one more break of serve thrown in with a couple of service holds.
Pliskova held her serve to narrow the deficit to 4-2, but one more break in the eighth game saw Kuznetsova even the match. In the final set, Kuznetsova lead 4-2 in the match, only to see Pliskova break back. A second break on the fourth seed’s serve in the eighth game gave Kuznetsova the chance to serve for the match that she failed to capitalise by giving back the break to her opponent.
Trying to stay in the match and bring the set back on serve, Pliskova didn’t falter and brought the match on level terms at 5-5. In the 11th game, it was Kuznetsova’s turn to be broken. With an opportunity to win the match, her second one on the trot here, in Singapore, Pliskova blinked and the match went into the tie-break.
Kuznetsova led 6-3 in the tie-break, but Pliskova saved all three match points only to lose the match on the fourth to give the tenacious Russian a 2-0 lead in the group. She has also qualified for her first-ever semi-finals in the season finale.
 Agnieszka Radwanska (POL) def.  Garbine Muguruza (ESP) 7-6 (1), 6-3 The defending champion finally notched her first win in the tournament, over fifth seed Garbine Muguruza sending the latter crashing out. Radwanska led in the first set 4-1, but Muguruza clawed her way back in to equalise the score at 4-4.
The set eventually proceeded into the tie-break in which the Pole was ruthlessly efficient as she secured the opening set with the loss of just one point in the tie-break. Muguruza broke early in the second set to lead 3-1, but lost the lead as Radwanska broke back to level the set at 3-3.
That was the end of Muguruza’s attempts to stave off ouster from the finals as Radwanska broke the Spaniard twice successively, including in the ninth game of the set that saw her capitalise on the two match points on Muguruza’s serve.
White Group Semi-finals' Qualification Scenarios The win keeps Radwanska in the hunt to qualify for the semi-finals. Svetlana Kuznetsova’s win means that she’s qualified at the top of the White Group. The second semi-finalist’s place boils down to the last round robin match between Karolina Pliskova and Radwanska.
The winner of that match will qualify in the second place from the White Group. Brief Scores Summary  Svetlana Kuznetsova (RUS) def.  Karolina Pliskova (CZE) 3-6, 6-2, 7-6 (6)
 Agnieszka Radwanska (POL) def.  Garbine Muguruza (ESP) 7-6 (1), 6-3 Also Read Where the Progress of the Australian Players?