Johanna Konta battled back from a set down to sink Sloane Stephens and reach the last 16 at Wimbledon.
The British number one appeared on the brink of defeat with former US Open champion Stephens, seeded nine, dictating the match and errors creeping into Konta's game.
But Konta managed to stop the bleeding and haul herself level before a composed final set wrapped up a 3-6 6-4 6-1 victory and extended her 100 per cent record against Stephens to four matches.
The most recent of those wins was a 6-1 6-4 pummelling at the French Open in May, where Stephens was overrun by Konta's energy and intensity.
It seemed she had learned a lesson from that painful defeat, with the American soaking up the power from Konta and moving her all around the court.
Konta's serve has improved immensely since last year, so much so that she had not been broken all week.
That changed in the eighth game of the first set, Stephens mixing things up with lobs, drops and powerful groundstrokes to force the pivotal break.
A loose forehand from Konta gifted Stephens two break points at 2-2 in the second, to her obvious frustration as she gestured angrily to her coaching team.
She managed to repel both, and then a third among six deuces for what looked an important hold.
Konta forced a break point, her first of the match, at 4-3 but, facing a second serve, wastefully pushed the return long and the chance disappeared.
The 28-year-old had to quickly put that setback behind her and, to her credit, she did, a comfortable hold followed by a break, at the second attempt, to level the match.
The 2017 semi-finalist had transformed the match. Suddenly Stephens' range had deserted her, and a rejuvenated Konta held to love before breaking twice to book a fourth-round meeting with two-time champion Petra Kvitova on Monday.
"She was playing incredibly well and I was fully prepared to be not coming back after that second set," Konta told the BBC.
"I was pleased I was able to keep battling, to keep with her, mix things up and get her out of that zone.
"It was incredibly tough out there, she's an incredibly good player. I really had to work hard to get myself into the match and get my level up to hers.
"Every round is trickier. I'm just really pleased to have come this far. I'm really pleased with the tennis I'm playing and looking forward to playing Petra, one of the best players in the world."
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