A beaming Madison Keys after victory over her
namesake and compatriot, Madison Brengle
Madison Keys advanced to her first grand slam quarter-final and underlined her pure hitting potential with a 6-2 6-4 victory over compatriot and namesake Madison Brengle on Monday.
Brengle had said before the match the pair had joked 'there can be only one' Madison if they ever met each other, with the clash also the first time since 2002 that two American women not named Williams had met this deep in a grand slam.
The 19-year-old Keys, who destroyed the hard-hitting two-times Wimbledon champion Petra Kvitova in the third round on Saturday, was equally as destructive against her 24-year-old compatriot, hammering 38 winners in the victory.
She will now meet compatriot Venus Williams in the last eight after the resurgent 34-year-old beat sixth seed, Agnieszka Radwanska, 6-3 2-6 6-1 in the other fourth round match.
Venus Williams delighted by her fourth round win over sixth seed, Agnieszka Radwanska
The seven-time Grand Slam champion who suffers from Sjogren's syndrome, an auto-immune disease that can cause fatigue, battled through to reach her first Grand Slam quarter-final since 2010.
Asked what had inspired her successful run in Melbourne, Venus said: "Definitely my sister Serena, she's just the ultimate champion.
"And definitely a lot of inspiration from all my fans who have stayed behind me through thick and thin."
Top seed Serena dug deep for a 2-6 6-3 6-2 win over Garbine Muguruza before returning later in the day to watch her sister in the night match on Rod Laver Arena.
Serena Williams next faces Slovakia's Dominika Cibulkova, who beat two-time champion Victoria Azarenka 6-2 3-6 6-3.
Video - Madison Keys vs Madison Brengle Australian Open 2015 Highlights: