Serena into semis, Wozniacki fights pain barrier

World number one Serena Williams marched into the semi-finals of the WTA Championships on Thursday with a comfortable win over Elena Dementieva while sister Venus kept her title hopes alive long after midnight.

Serena into semis, Wozniacki fights pain barrier

World number one Serena Williams marched into the semi-finals of the WTA Championships on Thursday with a comfortable win over Elena Dementieva while sister Venus kept her title hopes alive long after midnight.