Two-time US Open winner Tracy Austin has claimed that Wimbledon champion Serena Williams will be under "immense" pressure to secure the US Open and make history.
If Williams can go on to win the Flushing Meadows tournament, she would become the first person to win a calendar-year Grand Slam since Steffi Graf in 1988.
Austin told BBC Sport: "Looking ahead to the US Open, the pressure now on Serena Williams will increase hundred-fold.
"Winning the calendar-year Grand Slam has not been done since 1988. You have to think at 33 this might be the only time. With social media, everyone is talking about it and the pressure will be immense."
Williams currently holds the "Serena Slam" - the Australian Open, French Open, Wimbledon and the 2014 US Open.