For WTA Finals top seeds Martina Hingis and Sania Mirza, doubles tennis revolves around a single word: Trust.
It is faith not just in their own ability but also their partner's. It is, unlike a singles match, the assurance of a team-mate's support. It is skill multiplied by groupthink.
Down a break 1-3 in the first set of yesterday's semi-finals to sisters Chan Yung-jan and Hao-ching, their belief never wavered as they won 11 of the next 14 games to complete a 6-4, 6-2 victory against the third seeds from Chinese Taipei.
It was their fifth win in six meetings this season. It also stretched their winning streak to 21 matches.
Said Mirza, 28: "In a lot of tough moments, that trust we have in each other takes us through."
TURNING IT AROUND
We were down but were able to put our abilities together and lift it a notch just to be more involved and create more opportunities.
MARTINA HINGIS, on the pair's comeback from 1-3 down in the first set to win comfortably
Her partner is an incredibly positive person, noted Hingis, whose overhead smash on match point sealed an emphatic comeback.
"We were down but were able to put our abilities together and lift it a notch just to be more involved and create more opportunities."
Top doubles teams are often a study in opposites - the booming server and soft-touch net player, the firebrand and the cool tactician - and the No. 1 ranked Swiss-Indian duo (nicknamed fire and ice), are no exception.
Mirza's big forehand from the baseline complemented Hingis' feel at the net and despite contrasting outfits and colours, they were a picture of synchronised motion.
As for the Chans, wastefulness was an issue throughout the 83-minute encounter. They made 80 per cent of their first serves in the second set but won just 33 per cent of the points and were broken four times.
The siblings were dressed in matching navy blue but resembled lost strangers as they were repeatedly left flat-footed by their crafty opponents.
This is Hingis' first appearance in the final of the season-ender since 2000 while Mirza (previously with Cara Black) is seeking back-to-back championships in Singapore.
When Black decided to take a break from the game, Mirza joined forces with Hingis in March.
Their first training session a month earlier had been memorable for all the wrong reasons though. Chuckled Hingis, 35: "Worst practice in the world. It was windy and stormy in Doha and we got our ass kicked."
But on the court and in an official contest, it was them dishing out lessons. They won their first three tournaments and arrived in Singapore with eight titles, including Wimbledon and the US Open, and a formidable 50-7 win-loss record.
They will start as overwhelming favourites in today's final against the eighth-seeded Spanish pair of Garbine Muguruza and Carla Suarez Navarro, who beat Andrea Hlavackova and Lucie Hradecka 7-6 (8-6), 6-0 last night.
The past eight months have brought Hingis and Mirza closer together and the trust - a word that was mentioned five times by both women in their post-match press conference - between them has flourished.
Said Mirza: "We just feel like we complement each other great on the court. And when you compliment each other off the court as well, that's when you make a deadly combination."
Or to use an African proverb: "If you want to go fast, go alone. If you want to go far, go together."
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