Martina Navratilova proposes to girlfriend at US Open

Former world number one and 18-time Grand Slam winner Martina Navratilova proposes to her girlfriend Julia Lemigova at the US Open.

The 57-year-old's proposal was shown live on the Arthur Ashe stadium big screen following Kei Nishikori's surprise win over world number one Novak Djokovic.

The couple hope to marry in Florida, where a federal judge has ruled that the state's ban on gay marriage is unconstitutional.