Pegula ends Keys' dominance to reach Australian Open quarterfinals

  In the first fourth-round match in six years between two Americans at the Australian Open, Jessica Pegula ended Madison Keys' title defense on Monday with a 6-3, 6-4 victory.

"I've been playing really well, seeing the ball really well, hitting the ball really well throughout this tournament, and I wanted to stay true to that and rely on some of the things I thought she was going to do," Pegula said after the match, as quoted by the WTA.

Keys, who won her long-awaited first Grand Slam singles title in Melbourne last year, extended her unbeaten streak to 10 straight with three wins this year, while Pegula entered the match with a 3-0 record in the round of 16.