ABU DHABI, U.A.E. -- No.9 seed Maria Sakkari of Greece stormed back from a set down to eliminate No.1 seed Sofia Kenin of the United States, 2-6, 6-2, 6-0, and clinch a semifinal spot at the Abu Dhabi WTA Women's Tennis Open.

"Beating these players this week it means a lot," Sakkari told the press, after her win. "I'm playing players that I've never played, like [Muguruza] yesterday, so I have a better idea if I play them again. So in general it gives me a lot of confidence starting the year like that and I'm super happy to travel to Australia with some good matches with me."

It was World No.4 Kenin who had won their two previous encounters, which were three-set thrillers in the first round of 2018 Wimbledon and the second round of the 2018 US Open. This time, though, Sakkari charged back from the loss of a quick first set to dominate the final two frames and collect the win after 83 minutes of play.

Overall, Sakkari converted six of her 13 break points, and fired 23 winners, including nine aces, to Kenin's eight winners. The World No.22 reeled off the final ten games of the match to attain the upset victory.

"I think I was rushing a little bit too much at the beginning of the match," said Sakkari. "I didn't really know what I had to do once I saw that what I was doing wasn't working. I tried a different way that actually worked. I tried to be more solid and make more balls.

"I think I did way too many errors and I was hitting too big when I didn't have to. But I'm glad that once again I found the way to turn the match around."

Sakkari thus claimed the fifth Top 5 win of her career, and her second in her last three tournaments. She most recently claimed a win over a Top 5 player by ousting Elina Svitolina at Ostrava in October.

"I think that one of the things that really helped me is that I realized that my ball is pretty heavy," said Sakkari. "I have a lot of power and I have been using it the right way.

"Up until last year I couldn't really control my power so I had to take a little bit of pace off because I was hitting too hard and I was missing many shots. So I think I've found a way and I've found my real pace on the court. When I have an opportunity I go for it and that builds confidence."

Sakkari will now face No.4 seed Aryna Sabalenka of Belarus in the final four, after Sabalenka outlasted No.6 seed Elena Rybakina of Kazakhstan in Monday’s first quarterfinal. Sabalenka has defeated Sakkari in three of their four meetings, including twice in the Middle East last season, at both Doha and Dubai.

"[Sabalenka is] super confident now," said Sakkari. "We know each other really well, we practice a lot together. She's having a great career so far and she's really young. She's one of the toughest players to play out there. I beat her once so I think I can do it again. I'm not saying I will for sure, but it's going to be a very tough match for both."

It was Kenin who cruised through the opening stages of the match, breaking Sakkari twice early while romping to 4-1 without facing a break point. There were signs that Sakkari could stage a comeback in the opener after clawing one break back, at love, for 4-2, but the Greek let an error go wide to drop serve at love herself and cede the 5-2 lead to the top seed.

Opening the court up with ease, Kenin eased to double set point in the next game, then grabbed her second chance to polish off the set with an unreturnable serve, clinching the one-set lead by converting all three of the break points she held.

At 2-2 in the second set, though, the tables turned. After a brilliant love hold by Sakkari for 3-2, the players engaged in a protracted battle in the sixth game of the set. Kenin charged back from 15-40 down to push the game to five deuces, but Sakkari continued to send replies back with interest to get two more chances. On her fourth break point of the game, the Greek chased down a dropshot to force a wide error and earn a 4-2 lead.

Stellar serving brought Sakkari back from behind as she consolidated for 5-2, and the Greek refused to rescind her control of the set in the following game, blasting a backhand return winner crosscourt to reach double set point. On the second opportunity, Kenin pushed a backhand miscue into the net, and the match was all square at one set apiece.

Sakkari rolled towards victory after the second-set turnaround, clinching her second break of the decider with a forehand winner down the line for a 4-0 lead. A love hold for 5-0 was the Greek’s ninth straight game as she edged closer to victory.

Serving to stay in the affair, Kenin was unable to match the Greek, and after the American pushed a backhand miscue long, Sakkari was presented with triple match point. Sakkari slammed a return long to miss her first chance, but on the second, Kenin tapped a backhand error into the net, and the No.9 seed had won her tenth straight game to notch the upset.

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