'It's decimated': Glaring Ash Barty detail in WTA Finals photo

A new WTA Finals champion will be crowned in Guadalajara this week when a severely depleted field brings the curtain down on a tumultuous 2021 season.

World No.1 Ash Barty, four-time grand slam champion Naomi Osaka and American legend Serena Williams were notable absentees as the eight-player field gathered for photos in Mexico ahead of the WTA Finals.

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With Williams injured, Osaka on an extended hiatus and Barty opting to skip the event, an all-European field will be left to compete for the season-ending title.

With Barty the defending champion from 2019 after the event was cancelled last year because of the Covid-19 pandemic, a new champion will be crowned.

Only two of 2021's grand slam finalists have travelled to Mexico for the WTA finals - Barbora Krejcikova of the Czech Republic, the World No.3 who won the French Open in June, and compatriot Karolina Pliskova, beaten by Barty at Wimbledon.

The two teenage sensations who lit up the US Open - Britain's 18-year-old fairytale winner Emma Raducanu and Canada's 19-year-old Leylah Fernandez - both failed to qualify.

Six of the eight players in the field are playing in the WTA Finals for the first time, with Pliskova and Spain's Garbine Muguruza the only veterans.

The tournament, which is taking place in Mexico this year after being moved from its usual home in Shenzhen due to the pandemic, sees the field split into two groups of four.

The winners and runners-up of the groups advance to the semi-finals.

Aryna Sabalenka of Belarus starts the event as top seed, qualifying for the finals after a season which saw wins in Abu Dhabi and Madrid followed by runs to the semi-final at Wimbledon and the US Open.

Second seed Pliskova has yet to enter the winner's circle this season, with the highlight remaining her march to the final at Wimbledon.

Maria Sakkari of Greece, seeded five in Mexico, is also chasing her first title of the year.

As the only grand slam champion of the year in the line-up, the third-seeded Krejcikova could well emerge as the player to beat.

Poland's Iga Swiatek, a surprise winner of the French Open in 2020, is seeded fourth, looking to claim a third tournament of 2021 after wins in Adelaide and Rome.

Spanish sixth seed Muguruza, who failed to go further than the fourth round at a grand slam this year, is also chasing a third title after wins in Doha and Chicago.

Muguruza's compatriot Paula Badosa arrives in Guadalajara fresh from a confidence-boosting victory in Indian Wells last month, while Annet Kontaveit of Estonia rounds out the field after a breakout season in which she won three titles.

Ash Barty's sad withdrawal from WTA Finals

Barty announced last month that she won't play again in 2021, relinquishing her WTA Finals crown.

The Australian star pocketed the biggest cheque in tennis history for $6.4 million after winning the WTA Finals in Shenzhen in 2019.

The World No.1 hasn't played since the US Open in September, switching her full focus to preparing for the Australian summer and another tilt at her home grand slam in Melbourne.

"I wanted to let everyone know that I won't be competing in any further tournaments in 2021, including the WTA Finals in Mexico," Barty said in a statement.

"It was a difficult decision but I need to prioritise my body and my recovery from our 2021 season and focus on having the strongest pre-season for the Australian summer.

"With ongoing challenges of travelling back to Queensland and quarantine requirements, I am not willing to compromise my preparation for January.

"I wish the WTA team and the players all the best for a successful WTA Finals and the rest of the year."

Barty's coach Craig Tyzzer had previously hit out at the "ridiculous" conditions in Mexico.

"We only just found out it's in Mexico at 1500 metres (above sea level) and they're using pressure-less balls," Tyzzer told AAP.

"Pressure-less balls absolutely fly. It's a ball that if you use it in normal conditions, it doesn't bounce.

"In conditions they've never played, in a country they don't play and at altitude, I just feel it's ridiculous.

"As a spectacle, it's just frightening."

with agencies

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