No.5 seed Camila Osorio pulled off a big comeback to claim a massive upset at the Abierto GNP Seguros on Friday night. The 20-year-old Colombian defeated No.1 seed Elina Svitolina of Ukraine 1-6, 7-5, 7-6(5) to reach the semifinals in Monterrey.

In a match that finished well after midnight, World No.44 Osorio prevailed after 2 hours and 33 minutes, moving into her first semifinal of the season in just her third event of the year. Osorio came back from a double-break down in the third set to complete the stunner.

"I never gave up in any moment," Osorio said on court, after her win. "I was 6-1 down, and I just kept fighting, and I kept grinding point by point. I'm really proud of that."

Osorio is now 2-0 against Svitolina, the World No.15 and 2020 Monterrey champion. Osorio also fought back from a set down to upset Svitolina in the first round of Tenerife last year. Svitolina was the No.1 seed at that event as well.

Svitolina's undefeated record at the Abierto GNP Seguros came to an end. The Ukrainian is now 7-1 at Monterrey, having defeated Marie Bouzkova in the 2020 final in her only other tournament appearance.

Svitolina swept through the first set, claiming the last five games to grab the opener. But Svitolina was unable to put away Osorio's pinpoint hitting and sturdy defense in the second set, and the Colombian claimed the only break of that set at 6-5 to suddenly push the clash into a decider.

An up-for-grabs third set was seemingly in Svitolina's control as she charged to a 4-1, double-break lead. But Osorio scampered all over the court to win divine rallies and was rewarded with four games in a row and a 5-4 lead.

Svitolina stopped the winning streak with a hold for 5-5, and the pair moved into a decisive tiebreak. Svitolina led 3-0 in the breaker but Osorio came back once again, and at 5-5, Svitolina hit a poorly-timed double fault to give Osorio match point. There, Osorio punched a volley to close out a rally, and the upset was hers.

Earlier on Friday, two tussles which took over 3 hours apiece determined the event's first two semifinalists.

In Friday's opening match, No.6 seed Nuria Parrizas Diaz outlasted her fellow Spaniard, No.4 seed Sara Sorribes Tormo, 6-3, 1-6, 6-4 in 3 hours and 2 minutes.

In the first meeting between the compatriots, 51st-ranked Parrizas Diaz prevailed over last year's Monterrey semifinalist Sorribes Tormo, who is ranked No.36. With the victory, 30-year-old Parrizas Diaz reaches her first career tour-level semifinal after going 0-3 in her previous quarterfinals.

Parrizas Diaz will now take on Osorio in the semifinals.

An even longer match followed as Beatriz Haddad Maia toppled 2020 Monterrey runner-up Marie Bouzkova 4-6, 6-4, 7-6(7) in a grueling 3 hours and 22 minutes. Haddad Maia saved three match points in the third-set tiebreak, coming back from 3-6 down in the breaker to triumph.

Highlights: Haddad Maia def. Bouzkova

Haddad Maia, a recent doubles finalist at the 2022 Australian Open, is into her first tour-level singles semifinal since 2019. She is a win away from her second career Hologic WTA Tour singles final; she was a runner-up to Jelena Ostapenko at 2017 Seoul.

The Brazillian will face No.2 seed and defending champion Leylah Fernandez, after the Canadian closed out the night session with a 7-6(4)m 6-4 win over China's Wang Qiang.

Fernandez closed out her 1 hour and 47-minute win at 2:45 a.m. in Monterrey, but she expressed no concerns over her recovery ahead of the semifinal against Haddad Maia on Saturday night. 

"Is it really Saturday?" Fernandez joked on court. "I feel great, I'm ready for another match. I have a lot of energy so I can't wait to play today."

Hightlights: Fernandez def. Wang Qiang

Now on an eight-match win streak in Monterrey, Fernandez is into her first semifinal since her breakout run at the US Open last fall.