GUADALAJARA, Mexico -- The Race to the WTA Finals has come down to two players vying for the final qualifying spot for the Hologic WTA Tour's season-ending finale. And it will be decided Friday at the Guadalajara Open Akron. 

Seventeen players had a chance to grab one of the five remaining qualifying spots at the start of the week. After Day 4 in Guadalajara, four more players have sealed their places in Fort Worth: Coco Gauff, Caroline Garcia, Aryna Sabalenka and Daria Kasatkina. 

Who’s qualified

No.1 Iga Swiatek
No.2 Ons Jabeur
No.5 Jessica Pegula
No.7 Coco Gauff
No.10 Caroline Garcia
No.4 Aryna Sabalenka
No.11 Daria Kasatkina

Who’s still alive

The final qualifying spot will come down to either Veronika Kudermetova or Maria Sakkari on Friday.

Veronika Kudermetova (Race No.9): Kudermetova advanced to the quarterfinals on Thursday with a straight-sets win over Jelena Ostapenko

Maria Sakkari (Race No.10): Sakkari defeated Danielle Collins 5-7, 6-3, 6-3 on Thursday night to eliminate the American from contention and set up a one-match playoff against Kudermetova in the quarterfinals Friday. The winner of that match will clinch the final spot and set the elite eight for Fort Worth. 

"It was meant to be," Sakkari said. We both had very tough draws. It was not guaranteed that we were going to play each other in the quarterfinals. I think the passion, how much we want it, it got us to the point that we have to play each other just to get that one spot. It's going to come down to not who wants it more, but who plays a better match tomorrow.

"We both have good seasons. That's why we're fighting for that spot. I don't care what people say about my season that has been a roller coaster, but all I know is I'm still a Top 10 player. I'm still one of the two players that might get the last spot."

Sakkari leads the head-to-head 2-1 over Kudermetova, most recently winning their third-round duel at the Australian Open. 

In a must-win match against Collins, Sakkari engineered her sixth comeback win of the season to extend her record to 2-0 over Collins. Sakkari did well to bounce back from dropping the opening set. The World No.8 served for the set at 5-4 and had a set point, but Collins battled her way back to win the last three games of the set. 

But the lack of baseline consistency continued to plague Collins. Sakkari broke immediately to open the second set and held her serve for the remainder of the match, facing just two break points in the last two sets. With Sakkari managing her service games, Collins' own serve buckled under the compounding pressure.

Serving at just 47% first-serves in, Collins hit 11 double-faults in the match and had to face down 11 break points. Sakkari was able to break a total of five times and held her nerve down the stretch to seal the victory after 2 hours and 17 minutes. 

Watch This: Kalinskaya nearly wins a wild point with a broken string vs. Kasatkina

Closing out the night session, No.73 Anna Kalinskaya continued her strong week in Guadalajara by defeating No.11 Daria Kasatkina 6-2, 2-6, 6-3 to advance to her first WTA 1000-level quarterfinal. Kalinskaya , who already knocked out Barbora Krejcikova, Elise Mertens and Kasatkina, faces Marie Bouzkova next. 

Note: Race rankings based on the start of the tournament.