INDIAN WELLS, CA, USA - Belinda Bencic's excellent adventure continues in the California Desert; the former World No.7 shook off a tough challenge from No.5 seed Karolina Pliskova to win a 12th match in a row, 6-3, 4-6, 6-3, and reach her first BNP Paribas Open semifinal.

"I'm very confident," Bencic said after the match. "You know, I'm really just trying to take it one step at a time. Of course now it's been a few steps more. But, you know, I'm not putting pressure on myself even now. I'm just playing."

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After several years of injury struggles, Bencic kickstarted her season with a win at the Dubai Duty Free Tennis Championships - where she scored four straight Top 10 wins en route to the title. Celebrating her 22nd birthday in Indian Wells, she backed up her fourth round win over World No.1 and defending champion Naomi Osaka (and improved to 8-1 in three setters in 2019) after two hours and 16 minutes on Stadium 1 against good friend Pliskova.

"I said yesterday, the less I think on the court the better it is. When you're confident, you can really just trust your instincts and you don't have to think about it at all.

"I'm definitely playing how I feel it, and it's going well so I'm not planning on changing that."

The Swiss youngster had never played Pliskova before, but made the most of previous practice sessions to make a strong start on Thursday afternoon, breaking first and saving back-to-back break points to maintain her lead in the sixth game, grabbing one last break of her own to nab the opening set behind 14 winners to just six unforced errors.

Pliskova began the year with a 12th career WTA title at the Brisbane International and scored a shock win over Serena Williams to reach the Australian Open semifinals. The three-time WTA Ace leader had twice triumphed in three sets this week in Indian Wells, and the two-time semifinalist seemed poised to do just that as she raced to a 4-0 lead to start the second set.

Though Bencic clawed back to nearl-level, Pliskova's famous first serve took her through a titanic final game that saw her save a break point and convert her fifth set point opportunity. Taking more initiative throughout the second set, the Czech powerhouse hit 17 winners and 19 unforced errors to just nine each from Bencic.

"I was struggling, I think, a little bit with myself since the beginning of the match," Pliskova said. "Physically it was tough somehow today, and the wind didn't help much.

"So my serve was bad, my shots were bad," she continued with a wry smile. "I think still good that I fought, that it went to the third set. But otherwise, yeah, not even close to my good tennis."

The pair continued to battle through several long games to start the decider, most notably as Pliskova served at 1-2, fighting off four break points and eight deuces. Undaunted, Bencic dropped just one point in her next two service games and promptly broke the former No.1 at her next opportunity.

"I think I made great steps forward in the fitness side," Bencic said. "I definitely feel like I'm moving much, much better on the court than I have ever moved.

"I actually never feel like I'm getting tired or, like, more tired than my opponent on the court. I think that was the huge improvement. I think you definitely need it against the top of the world to be just incredibly fit and not just, like, one week but obviously many weeks in a row."

Undefeated since Fed Cup weekend - where she earned two singles wins over Italy's Camila Giorgi and Sara Errani - Bencic extended her winning streak to 12 with a confident hold to 15, booking her first Premier Mandatory semifinal.

Standing between Bencic and a second straight final will be the winner of the last quarterfinal between former No.1s Angelique Kerber and Venus Williams later tonight.

"Both are very tough. I played Angie this year in Hopman Cup, and Venus, the last time was at the Australian Open [in 2018]. Obviously, it's incredible to play these kind of champions in semifinal of Premier Mandatory tournaments.

"Like, it will be of course huge respect to all my opponents. Yeah, I will see."