No.8 seeds Nicole Melichar-Martinez and Ellen Perez had to battle into the GNP Seguros WTA Finals Cancun doubles final, holding off numerous fightbacks by No.7 seeds Gabriela Dabrowski and Erin Routliffe before emerging with a 6-1, 6-7(1), [10-6] win on Sunday.

In the final, Melichar-Martinez and Perez will face No.6 seeds Laura Siegemund and Vera Zvonareva, who won twice on Sunday over the top two-seeded teams.

WTA Finals: Scores | Draws | Order of play

In the first match of the day, Siegemund and Zvonareva finished off group play with a 3-6, 6-4, [10-8] win over No.1 seeds Coco Gauff and Jessica Pegula. Hours later, Siegemund and Zvonareva toppled No.2 seeds Storm Hunter and Elise Mertens in the semifinals 3-6, 6-3, [10-5].

In the prior meeting between the two Cancun finalist teams, Siegemund and Zvonareva beat Melichar-Martinez and Perez 6-4, 3-6, [10-6] in this summer's Washington D.C. quarterfinals.

Back in a final: American Melichar-Martinez and Australia's Perez are into their fifth final of the year after their 1-hour and 37-minute semifinal victory. Melichar-Martinez and Perez are seeking their first team title of 2023, having gone winless in their four previous team finals this year.

Melichar-Martinez and Perez served for the match at 5-4 in the second set, but reigning US Open champions Dabrowski and Routliffe made their first comeback of the day, pushing the second set into a tiebreak.

Powerful returning by Dabrowski and Routliffe allowed them to cruise through the second-set breaker and line up a decisive 10-point match-tiebreak.

In the match-tiebreak, a stirring forehand return winner down the line by Melichar-Martinez kicked off a dominant stretch by her and Perez, as they built a 7-2 lead. But Dabrowski and Routliffe worked their way back into contention once again, pulling all the way back to 7-6.

This time around, though, Melichar-Martinez and Perez did not yield, with Perez cracking a forehand return winner down the line to stop the streak of points against them and lead 8-6. A huge Melichar-Martinez return set up triple match point at 9-6, and Melichar-Martinez converted the first chance with a winning volley.

Siegemund and Zvonareva pick up two daytime wins: Later on Sunday, Siegemund and Zvonareva booked their spot in the final with a 1-hour and 27-minute win over Hunter and Mertens.

Siegemund and Zvonareva are into their fifth team final of the season -- all coming in the last three months. They are now a win away from their fourth team title of the year, having already picked up trophies in Washington D.C., Ningbo and Nanchang.

Siegemund and Zvonareva were also runners-up at this year's US Open -- a title they won together in 2020, in their first event as partners. In that 2020 US Open final, they beat Melichar-Martinez and her partner at the time, Xu Yifan.

In Sunday's second semifinal, Mertens fired a forehand pass down the line to earn her team’s third service break of the day and wrap up the first set.

But Siegemund and Zvonareva accumulated three service breaks in the second set, leveling the match when Mertens double faulted on the fourth set point of the 5-3 game.

Siegemund and Zvonareva carried that momentum all the way through the match-tiebreak on their way to the narrow victory. Siegemund and Zvonareva had one less winner than Hunter and Mertens, but the victors also had six fewer unforced errors than their opponents.

Despite the semifinal loss, Hunter will still claim the WTA Doubles World No.1 ranking and the year-ending No.1 position for the first time next week.

Siegemund and Zvonareva weren't even in the semifinals when the day began. They kicked off Sunday by edging past Gauff and Pegula in the last round-robin match of the week.

Play was suspended due to inclement weather on Friday night with Gauff and Pegula leading 6-3, 1-1, and persistent rain forced the conclusion of the match all the way to Sunday. 

Upon resumption, it was Siegemund and Zvonareva who took charge and ousted the top seeds. The win allowed Siegemund and Zvonareva to finish group play 2-1 and claim second place in the Mahahual Group, sending them into the semifinals.