Britain's Jamie Murray and American partner Bethanie Mattek-Sands are through to the semi-finals of the mixed doubles at the Australian Open.

The US Open champions beat China's Saisai Zheng and Belgium's Joran Vliegen 6-3 6-4.

They saved six break points, including two while serving for the match.

It is the first time Murray has reached the last four in the mixed doubles in Melbourne but Mattek-Sands won the title in 2012 with Horia Tecau.