Sabalenka's struggles with the serve are nothing new. The Belarusian produced a total of 80 doubles faults in her opening five games of the season, but is happy to see that figure going in the right direction.
Despite her troubles, the player booked her spot in the next round following a 4-6 6-3 6-1 victory over Vondroudova.
In her post-match interview, Sabalenka said: "I'm really happy right now, and mostly really happy that I made only 10 double faults."
"I'm just trying to stay positive, and it's working. I wasn't really thinking a lot about my serve. Maybe because the last matches I was able to break a lot of games. It gives me a little confidence on the returning games. That's why maybe I served better today."
Waiting for her in the Last 16 is Estonia's Kaia Kanepi who powered past Australia's Maddison Inglis.
Sabalenka will be hoping for further improvement with her serve ahead of that all-important clash with Kanepi.
The 23-year-old admitted that the mental aspect of her game will be key as she puts her trust in muscle memory.
She said: "I think its more mental because I put a lot of pressure on myself about my serve. The last matches I was trying to control everything with my serve, my legs, my arm, the ball toss. I was overthinking. I just stopped thinking.
"Today for example, I was only focusing on the good jump and that's it. Because I have this muscle memory, I trusted myself today much more than in first matches.
"It's good to know that you only have one problem. It's easier to fix than your whole game."