Winner ... Victoria Azarenka celebrates her victory over Angelique Kerber. Photo: Getty Images
This was a women's match-of-the-year candidate, just when one was needed. A marvellous three-set, three-hour exhibition at the WTA Championships, in which top seed Victoria Azarenka saved two match points against gallant German Angelique Kerber before a Turkish crowd worthy of the contest.
As the women's tour seeks a new venue for its flagship event from 2014, and also searches for a new major sponsor, it could scarcely have ordered a better advertisement. Kerber hit 49 winners to Azarenka's 45, including eight aces, but the Australian Open champion prevailed 6-7 (11-13), 7-6 (7-2), 6-4 after twice staring down defeat at 4-5 in the second set.
The first tiebreak equalled the longest in championships history, Steffi Graf and Lindsay Davenport having played the most recent to extend to 24 points, back in 1996. The match also ties the tournament games-played record of 36, and it is the third match to last that long - joining Justine Henin's 2003 defeat of Anastasia Myskina and Arantxa Sanchez Vicario's quarter-final eclipse of Jana Novotna a decade earlier.
So close ... Angelique Kerber returns the ball to Victoria Azarenka. Photo: AFP
As Maria Sharapova and Agnieszka Radwanska then started a match that was expected to stretch into the early hours of Thursday, Azarenka had moved to within one round-robin victory of securing the year-end No 1 ranking. But on a night that saw racquets bounced and broken, the contrast with the opening match was stark.
"I feel really proud that I was part of this match," Azarenka said.
"Maybe [it] didn't seem so good when you are in the court when you miss couple of shots. Doesn't seem as pretty. But I felt that the match was really high quality from both of us from the first point to the last."
Serena Williams was the first player to record two wins in this, the round-robin phase of the tournament, but her 7-6 (7-2), 6-3 defeat of Li Na had no-one searching for any superlatives. The usually incomparable Williams served horribly in a scrappy, error-riddled encounter, battling with her own emotions as well as Li, who claimed four of the first five games. When consecutive double-faults handed the Chinese a break for 3-1, the 15-time grand slam champion could not contain her frustration, a rare broken racquet earning Williams a warning for racquet abuse.
"I lost serve today more than in all of Wimbledon. It just wasn't a good serving day for me," said Williams, whose six aces were cancelled by an equal number of double-faults. "I was just thinking about it too much. I just need to not think and just play."
The upside was that she won anyway, and a semi-final beckons.
"Knowing I was able to win still with, for me, zero serve compared to how I normally serve, I think it's something good I can take out of the match," she said.
Williams has now won 45 of her past 47 matches, preparing for this tournament with coach - and rumoured new beau - Patrick Mouroutoglou during an extended stay in Paris, in a departure from her usual late-season routine.
"It is the first time, but when you've been playing professional (tennis) for 15 years you need a change sometimes. I feel like I welcome it. Usually I'm in the States and I'm doing this and that and that. For me it was nice to do and try something different. You know, it keeps me excited and it keeps me motivated. It's almost like I'm starting over. When you first come out on tour you have so much excitement and you're so hungry because everything is kind of new. I feel like it's all coming back like that for me."
So tonight comes Azarenka, in what has been billed as the marquee match of the round-robin phase: the numerical No. 1 against the player acknowledged as the best in the game. Serena, who has won 10 of the pair's 11 matches, against Vika, who has not lost since Williams beat her from 3-5 down in the third set of the US Open final.
"She's playing well. She's had a stellar year," said Williams. "I don't want to lose whether it's against her or whether it's against anybody else."
Australian Sam Stosur will play her opening match of the Championships tonight against Sara Errani, having replaced ill defending champion Petra Kvitova in the eight-woman field.
Order of play, Thursday:
 Angelique Kerber (GER) vs  Li Na (CHN)  Victoria Azarenka (BLR) vs  Serena Williams (USA)  Samantha Stosur (AUS) vs  Sara Errani (ITA)