MADRID, Spain - Kiki Bertens may not be able to defend her Mutua Madrid Open title next month in the Spanish capital's Caja Mágica - but the World No.7 is making a stellar effort from her sofa in the Netherlands, edging out Belinda Bencic 6-4 in the first of the tournament's Virtual Pro quarterfinals.

Later, the Dutchwoman was joined by Sorana Cirstea, who came within two points of defeat to Bianca Andreescu and trailed in the deciding tiebreak, but roared back to seal a 7-6(4) victory.

With Bertens' microphone not working, the defending champion left the in-match commentary to Bencic, who more than made up for it. "This is more frustrating than tennis," exclaimed the Swiss player after a Bertens volley landed for a winner. "It's like real life against you," she said ruefully after watching a pair of aces fly past.

The Bertens serve was indeed on song - but despite Bencic's complaints that she was "hitting too soft", the World No.8 managed to keep pace with her opponent as the first nine games passed without so much as a break point hoving into view. Up 5-4, though, Bertens struck, breaking Bencic to love and sealing victory with a defensive flicked forehand winner.

Afterwards, Bertens admitted that she had felt some pressure to up her skill level. "The thing is, I'd never played on a PlayStation before so I had no idea how it was working," she admitted. "Once I received it I knew I had to practice. I felt also I had to because I have to defend my title, and I heard all the other girls were practising!"

Cirstea and Andreescu would also turn in serve-dominated performances - "That's not typical," commented the Canadian drily - in which they rode waves of associating and dissociating from their avatars. "I'm trying to do what I try to do on the actual court," remarked Cirstea after hammering one of a series of backhand down the line winners. "I practised my net skills - let's see if they're going to come in handy today," Andreescu, who has yet to play the real-life Madrid tournament and for whom this was a debut of sorts, proclaimed in the early stages of the match.

At times, the pair appreciated their computer representatives' skills - "I like these angles, I wish I could use them in real life," said an impressed Cirstea - but there was frustration, too. "How bad is she?" exclaimed the Romanian mere games later. "My girl is lazy today. Too many matches in a row, she's tired." Meanwhile, Andreescu was deploying questionable shot selection. "Why is my player only slicing the return?" she asked. "That's not a good tactic, and I'm not even pressing that button."

Ultimately, though, there were good vibes as the match drew to a tight finish. There would be no breaks of serve, but Andreescu would conjure up consecutive return winners to take a 0-30 lead at 6-5 - only for Cirstea to hold and force the tiebreak with a "sick pickup", as Andreescu described it. There, the World No.6 would take a 3-1 lead, but - retrieving lobs and powering through her backhand - Cirstea reeled off six of the final seven points to book her place in the last four.

Afterwards, the World No.75 admitted: "I was more nervous today than usually on court. Finally I'm in my first Madrid semifinals!"