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Kerber was on her own hot streak - two weeks ago she won the Bank Of The West Classic in Stanford, her fourth Premier-level title of the year after triumphs in Charleston, Stuttgart and Birmingham.
And the No.11-seeded German put up some major resistance on Tuesday, rallying from 1-5 to 5-all in the first set and 1-3 to 3-all in the second set, but at the tail end of both sets it was Bencic who came through every time, and she reeled off the last seven points of the match to close it out, 7-5, 6-3.
"The first set was a very difficult situation - I had 5-1 and I was playing great, but then she played better and better and started going for her shots more until it was 5-all again," Bencic described.
"But then I was able to focus again and won my service game, and then I closed it out."
The key stat to the match, other than the fact that Bencic had 23 fewer unforced errors than Kerber (25 to 48), was the Swiss teenager's incredible conversion rate on the big points - she won a whopping six of her seven break point opportunities in the match, while Kerber converted on only three of 11.
Maybe her already-steely nerves are even steelier after those six huge wins in Canada?
"Last week was very mental - I'm so happy I was so mentally tough there," Bencic said.
"I had a lot of nerves against Serena in the semifinals, and I'm really happy I could close it out. It's just amazing for me, everything that's happened, and I'm really proud that I managed to win there.
"You get confidence when you keep winning, and especially when you're playing and winning on the big courts against the big players, so hopefully I can just keep going like this."
Has she been able to sleep since that breakthrough result?
"I've been sleeping very well, actually!" she smiled.
Bencic will play Flavia Pennetta in the next round. Pennetta won the pair's only previous meeting.