MIAMI (Reuters) - Aryna Sabalenka, back on court for the second time in as many days following the apparent suicide of former boyfriend Konstantin Koltsov, had a difficult and emotional week come to an end on Saturday with a 6-4 1-6 6-1 loss to Anhelina Kalinina.
After a gutsy second round win on Friday over good friend Paula Badosa the world number two appeared to have little left in the tank physically, mentally or emotionally for a late night Stadium court battle with Ukrainian Kalinina.
When her return wide gave Kalinina the match the 25-year-old Belarusian bowed her head, took a few steps then flew into a rage, venting her frustration by smashing her racquet to pieces at centre court.
With racquet destroyed, she then turned and walked off court without shaking the Ukrainian's hand.
"It's always tough to play on big stages against these top players," said Kalinina. "Today was really tough with nerves but I managed in the tough moments to deal with it.
"So I'm a little bit proud of myself today."
The result and outburst are hardly a surprise coming at the end of a pressure-packed week for the Australian Open champion.
Sabalenka issued a brief statement on Wednesday saying her "heart was broken" by the "unthinkable tragedy" but has otherwise remained out of the spotlight.
The statement was also the first mention since the tragedy that the couple had split.
The Miami-Dade police department confirmed on Tuesday that they had responded to a call the day before at a Miami resort about reports of a man jumping off a balcony. The police said no foul play was suspected.
Koltsov, 42, played for the Belarus national team at the 2002 and 2010 Olympics and spent parts of three seasons with the National Hockey League's Pittsburgh Penguins between 2003 and 2006.
The news of Koltsov's death sent a shockwave through the Miami Open as Sabalenka's fellow players rallied around her, including her opponent Badosa.
Sabalenka was very much in control of her emotions and slowly found her form in a 6-4 6-3 win over Badosa but slowly unravelled against Kalinina and could never regain her composure.
Her usually reliable forehand never consistently hit the mark while managing six double faults against just three aces.
"I missed a lot of opportunities, she started to play more aggressive in the second set," said Kalinina. "I think she played really, like, she stepped in and did some incredible, like, very fast rallies.
"But third set, yes, I was also more aggressive. That was my goal."
(Reporting by Steve Keating in Miami. Editing by Peter Rutherford)