World number one Angelique Kerber has gone through round robin unbeaten at the WTA Tennis Finals in Singapore.
The German has eliminated Madison Keys 6-3 6-3 a result that also sees Dominika Cibulkova advance to the last four.
The Slovak ousted Simona Halep 6-3 7-6.
Kerber says it's great to qualify for the semis unbeaten.
She says it givers her a lot of confidence to know she has won three matches to get through to the semis.
The winner of Karolina Pliskova against Agnieska Radwanska tonight will join already qualified Svetlana Kuznetsova in the semis.