Madison Keys has revealed that the thigh problem that she suffered during her three-set win over Venus Williams was similar to the injury that she had at last year's Wimbledon.

Keys reached the Australian Open semi-finals after playing through the pain barrier against the seven-time Grand Slam winner, but the American, who will now move into the top 20 in the WTA rankings, has admitted that she feels fortunate to continue her impressive run at the tournament.

The 19-year-old told reporters: "It was definitely kind of a flashback to Wimbledon for me. I have had some problems with that part of my leg, so it was kind of an overwhelming moment.

"It was kind of scary but luckily I was able to catch it before I did any real damage to it."

Keys will now play Venus's sister Serena for a place in Saturday's final.