Madison Keys has earned a place in the quarter-finals of a Grand Slam for the first time after beating Madison Brengle 6-2 6-4 in the fourth round of the Australian Open.
Keys, who recorded victories over home favourite Casey Dellacqua and fourth seed Petra Kvitova on her way to setting up the all-American clash, made the perfect start as she broke her compatriot's serve in the opening game.
Despite matching Keys for long spells, Brengle's struggles with her first serve offered chances to her rival throughout the match, and she was fortunate to be broken just twice in the opener.
However, the two breaks would be enough for Keys, whose serve carried her through when unforced errors threatened to open the door to Brengle.
The 19-year-old, who is coached by three-time Grand Slam singles winner Lindsay Davenport, displayed an exceptional ability to find the right angle for winners, and she was rewarded when she converted a break point at the fifth attempt in the third game of the second set.
It looked like the beginning of the end for Brengle, but she responded swiftly to immediately break back and started to play some of her best tennis to keep the match alive.
The late rally from Brengle was effectively over in the ninth game when Keys broke again, and she held her nerve to clinch the victory with a third match point a few moments later.