BOGOTA, Colombia -- No.6 seed Amanda Anisimova of the United States fought past a challenging opponent on home soil to reach the Claro Open Colsanitas semifinals, overcoming fellow 17-year-old Maria Camila Osorio Serrano of Colombia, 6-2, 1-6, 6-3, on Friday night.

The World No.76 needed all of her mettle to get past the talented 438th-ranked wild card and an excitable crowd supporting their countrywoman, but Anisimova was finally able to shake off off a poor second set to clinch her hard-earned victory after one hour and 51 minutes of captivating tennis.

"It was a really tough match, obviously," Anisimova told the media, after the match. "Playing someone in their country is really tough. So, I’m really happy that I battled through it, and mentally I stayed strong. [Osorio Serrano is] a great player and I have a lot of respect for her, so I’m really happy with the win."

Photos: Vive la difference! 16 titles, 16 winners in 2019 so far

32 winners came off the racquet of Anisimova in the match, compared to just nine for Osorio Serrano. However, the American also had 55 unforced errors, nearly double the Colombian's amount of miscues. Nevertheless, Anisimova was able to stave off trouble when she needed to most, saving 13 of Osorio Serrano's 17 break points the Colombian had during the clash.

Anisimova will face off against Brazilian qualifier Beatriz Haddad Maia in the final four. Haddad Maia upset No.7 seed Sara Sorribes Tormo of Spain, 6-7(6), 6-2, 6-3, earlier on Friday. It will be the first meeting between Anisimova and Haddad Maia.

"I’ve been playing well here, I’m going to keep doing what I was doing, and we’ll see how it goes," Anisimova stated.

Anisimova struggled through the opening game of the match, as the crowd vociferously cheered on their home favorite from the very first point. But the American was able to survive three break points and hold on, and then stole the next game from under the young Colombian’s nose, breaking for 2-0 with a return winner after Osorio Serrano led 40-0.

Osorio Serrano hung with Anisimova from the baseline for the rest of the first set, but Anisimova kept composed, staving off two more break points before holding for 4-1 with a backhand winner.

Anisimova then closed out her one-set lead in style, breaking Osorio Serrano at love as she finished off the opening frame with a wicked forehand return winner down the line. Anisimova’s nine winners in the opening stanza tripled Osorio Serrano’s count, while the Colombian rued going 0-for-5 on break points.

In the second set, though, Anisimova’s composure went missing, while the grit and defense of Osorio Serrano stayed sturdy. Anisimova’s difficult second set was signaled from the outset, as she squandered a 40-15 lead in the first game, handing Osorio Serrano a break point with a double fault, then dropping serve with a forehand error.

Osorio Serrano cruised through the second set from that point forward, breaking Anisimova three times and never facing a break point. The American’s forehand failed her in the stanza, as plentiful errors from that side allowed the Colombian to easily tie the match at one set apiece. Anisimova had one more winner but 14 more unforced errors than her opponent in the set.

Quickly, though, Anisimova regained her top play for the start of the decider. The American found the range on her forehand to break in the first game, then went up a double break for 3-0 after strong returning brought her to break point, where Osorio Serrano double faulted.

Anisimova gave one break back in the following marathon nine-deuce game, ending the game with consecutive double faults. Osorio Serrano saved a break point to hold for 3-2, then held at love to stay within one break at 4-3, giving her and the crowd hope. The young Colombian had pulled off a similar comeback when she won the final six games in her second-round victory over Kristie Ahn.

Anisimova was in dire trouble in the next game, down 0-40, but she used fierce forehands to eke her way out of that jam and pull off a stunning hold for 5-3. Osorio Serrano finally succumbed to powerful returning by Anisimova in the next and final game, as the American clinched a topsy-turvy win to book her spot in the semifinals.