"It's always tough to get some matches at the beginning of the season, so I'm happy I won two matches here and I hope to go even farther," Bertens said in her post-match press conference.
Voskoboeva spent two years off the tour nursing persistent foot injuries, and had just won her first WTA main draw match since 2014 ahead of her clash with Bertens. The top seed, by contrast, is in the midst of a career-best 12 months, having reached the semifinals of the French Open to qualify for her first Olympic tennis event.
"It was an OK match today; she helped me a lot in the beginning with a lot of mistakes, but in the second she played really well. I had to fight for it and there were some tough conditions with the wind, but I'm happy I got through.
"I really need some matches; my body needs matches to play better. You saw what happened last year in Paris: I won a tournament the week before and was in the semis the week after!"
Bertens rushed out to a 4-0 lead to start the match, serving out the opening set before things got complicated in the second. The Kazakh pushed Bertens to the brink on multiple occasions, leading by a late break in the sixth game. But the Dutch star roared back, winning the last three games to book an encounter with qualifier Elise Mertens.
"I know her well; she's a great young player with a good run last year. I'll have to be more aggressive than today but hopefully I can get the win."
"In the first set, she played well and I couldn't hit a strong ball," she explained after the match. "After that, I tried to focus on my forehand and things got better from there."
Safarova won a titanic sixth game in the first set and broke to start the second, but the 22-year-old won six of the last seven games to level the match.
"I started the match really well," Safarova echoed in her post-match press conference. "I had some game points to go 3-0, but things started going the other way. It wasn't easy conditions with the wind; she started to pressure me more and make fewer mistakes. I lost my rhythm; I tried to hang in there but it was always tough serving in this wind."
The Czech veteran showed signs of life late in the match, breaking Ozaki as she served for the upset, but the Japanese youngster broke serve one last time, reaching her third career WTA quarterfinal in two hours, 22 minutes.
"These conditions don't really suit my game because I like to be aggressive, but I was making too many mistakes. She was putting a lot of balls back; she ran and served well, especially at the end. This isn't the result I would have liked, but it's tennis and things happen. It's good that I got an extra two matches before Melbourne. Hopefully I'll peak there."