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.
