Alexei Popyrin is locked in a tight battle with Yoshihito Nishioka in a bid to reach the semi-finals of the Adelaide International.
Popyrin has embarked on a dream run so far at the event, qualifying for the main draw before taking out second seed Felix Auger-Aliassime and winning through to the quarter-finals.
Nishioka, the world No.36, presents another stiff challenge for Popyrin, but one the Australian looked more than up to early.
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Popyrin secured a break early in the match and appeared to get under the skin of Nishioka, who took issue with a line call during a change of ends.
That rant led to the ATP supervisor being called to the court, with Nishioka continuing to express his frustrations.
“You don’t change anything. That was a very important point and they don’t change anything and now I’m losing,” he said to the supervisor.
“There was a chance to break his service game but he took it.
“Chair umpires never say, ‘I’m wrong.’ They always say ‘I’m right, that’s wrong’. That’s crazy. It always happens, this conversation.”
Channel Nine commentator Roger Rasheed said watching on: “For someone who’s 36 in the world and 27 (years old), it’s a little bit disappointing he’s taking this long to get through his rant.”
Still, Nishioka managed to steady himself mentally, getting the break back and eventually forcing a tiebreak.
He took that tiebreak to silence the Adelaide crowd, but they found their voice when Popyrin broke serve early in the second.
Like the first set, Nishioka would break back and eventually bring the set into a tiebreak.
Despite going ahead early, Nishioka found himself reigned in by the Australian, who had a set point opportunity on his serve but failed to convert.
Chasing down a drop shot helped deliver Popyrin another opportunity on his own serve and a long shot from Nishioka delivered the second set to Popyrin and forcing a decider.
UNITED CUP – Order of play (all times AEDT)
Poland vs USA
Matches start from 10am
Iga Swiatek (POL) vs Jessica Pegula (USA)
Kacper Zuk (POL) vs Frances Tiafoe (USA)
Greece vs Italy
Matches start from 7pm
Maria Sakkari (GRE) vs Martina Trevisan (ITA)
Michail Pervolarakis (GRE) vs Lorenzo Musetti (ITA)
ADELAIDE INTERNATIONAL – Order of play (all times AEDT)
Centre Court
Matches from 11:30am
Marketa Vondrousova vs Aryna Sabalenka (2)
Not before 1:30pm
Jannik Sinner vs Sebastian Korda
Daniil Medvedev (3) vs Karen Khachanov (8)
Not before 7pm
Ons Jabeur (1) vs Marta Kostyuk
Not before 9pm
Novak Djokovic (1) vs Denis Shapovalov (7)
Showcourt 1
Matches from 11:30am
Yoshihito Nishioka vs Alexei Popyrin
Not before 1:30pm
Irina-Camelia Begu vs Veronika Kudermetova (4)
Linda Noskova vs Victoria Azarenka
