Top seed Aryna Sabalenka out of WTA Finals after Maria Sakkari’s epic win
Sakkari set up a semi-final against Estonia's Anett Kontaveit after outlasting Sabalenka 7-6 (7/1), 6-7 (6/8), 6-3 in 2hr 47min.
"It was a rollercoaster match from both of us," Sakkari said.
"It was just a matter of who took the…