MADRID -- World No.2 Aryna Sabalenka advanced to the Round of 16 at the Mutua Madrid Open after defeating Colombia's Camila Osorio 6-4, 7-5 on Saturday. A champion in 2019, Sabalenka will face 16-year-old Mirra Andreeva for a spot in the quarterfinals. 

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"I'm happy with the win," Sabalenka said. "She's a great player and she fought for every point. It was a really great match."

Coming off a strong 6-4, 6-3 win over Sorana Cirstea in her opening round, Sabalenka held off a spirited challenge from Osorio. Now ranked No.115 and coming off a one-month injury break, Osorio made good on her main-draw wild card to advance to the third round of Madrid for the first time. 

Sabalenka's power game ultimately proved too tough to solve for Osorio. After falling behind an early break at 3-1, Osorio gamely battled her way back into the match. She fended off two break points to close the gap to 3-2 and then, with the Spanish crowd behind her, the 22-year-old broke Sabalenka to level the first set. 

Sabalenka quickly settled herself after her error-prone stretch. She broke Osorio for a second time to lead 5-4 and held her nerve in a deuce game to serve out the opening set.

With a set in pocket, the reigning Australian Open champion clinically moved through the early stages of the second set. After Sabalenka built a double-break lead at 4-1, Osorio took a medical timeout to assess her left hip and leg. On the resumption, Osorio broke Sabalenka for the first time in the set and closed the deficit to 4-3. Osorio continued her march towards a comeback, breaking Sabalenka again as she served for the match at 5-4.

"That's something that I expected, especially against players like her," Sabalenka said. "She can return, she can play long rallies, and she can come back to the match. I just kept telling myself I have to keep going for my shots and I just have to make her move because she's not going to move all day long. Once I will get this approach shot and I will be able to finish the point.

"So I was just telling myself to keep going for my shots and don't start panicking."

That would be as far as Osorio's comeback would go. Smartly opting to keep the points shorter, Sabalenka pounded her way to a fifth and final break of Osorio's serve to earn a second opportunity to serve out the win. This time she did not falter. Sabalenka coolly served out the win to seal the match after nearly two hours.