Spain's Paula Badosa ground out a 7-6(4) 6-4 victory over Maria Sakkari at the WTA Finals in Guadalajara, Mexico on Saturday, moving to the top of Group Chichen Itza with two wins from two games.

Facing one of the WTA Tour's great battlers, the seventh seeded Badosa showed she can also play with grit during a two-hour, four-minute slugfest in the Mexican heat stretching her winning streak to eight matches.

Badosa blasted 10 aces past her Greek opponent and kept her under pressure, converting three of 12 break points.

Sakkari could not consistently find the mark, committing 49 unforced errors compared to just 22 from Badosa.

The victory put Badosa top the group with a 2-0 record, followed by Sakkari on 1-1 and Aryna Sabalenka and Iga Swiatek at 0-1.

Top-seeded Sabalenka and number five Swiatek clash later on Saturday.

"I suffered but I knew I was going to suffer against a player like Maria, she is an amazing fighter," said Badosa, who will celebrate her 24th birthday on Monday.

"I think the key was to fight as well, I'm the same as her I am a competitor, I like to compete.

"I had to stay very aggressive but here it is tough because of the altitude.

"I stayed aggressive and focused and fighting a lot and I think that was the game plan."

Sakkari underlined her warrior reputation, clawing her way back from 5-2 down in the first set to force it to a tiebreak.

But the fourth seed quickly lost the momentum when Badosa roared in front 4-0 on her way to claiming the breaker 7-4.

Badosa kept up the pressure in the second, securing the early break to jump in front 2-1.

A reeling Sakkari had to dig deep to keep from falling into an even bigger hole, fighting off six break points before holding serve at 3-2.

Sakkari finally got the break she needed to level at 4-4 but Badosa immediately broke back, then served out the match, clinching the victory on her third match point with a backhand winner.

(Reporting by Steve Keating in Toronto. Editing by Toby Davis)