Daniil Medvedev and Andrey Rublev produced ruthless performances as Russia cruised into the ATP Cup semi-finals.
Russia followed up their day-one win over Argentina with victory against Japan to ensure they will finish top of Group D.
Rublev got things rolling with an emphatic 6-1 6-3 win over Yoshihito Nishioka and Medvedev dispatched Kei Nishikori in a 6-2 6-4 triumph.
Those results meant the subsequent doubles match – which Japan won – would not be relevant.
"I am really happy for the team," said ATP Finals champion Medvedev, who has now won 12 matches in a row on the tour.
"Reaching the semi-finals is a big step – I am really happy that we made it in both singles. Both matches were straight sets, so really happy for the team and hopefully we can go further than that."
Italy, who had beaten Austria on the opening day, are also through after Fabio Fognini and Matteo Berrettini earned wins in straight sets over France duo Benoit Paire and Gael Monfils on Wednesday.
France play Austria next but neither team can catch Italy in Group C.
Alexander Zverev won a thriller against Denis Shapovalov 6-7 (5-7) 6-3 7-6 (7-4) to ensure Germany defeated Canada.
It was a first win at the ATP Cup for US Open runner up Zverev, who had a miserable tournament in 2020.
That sets up a day three contest for Germany against Novak Djokovic and Serbia where the winning team will progress to face Russia.
KYRGIOS AND WAWRINKA THROUGH
Nick Kyrgios – playing his first tournament for a year – made it two wins from two at the Murray River Open, defeating fellow Australian Harry Bourchier 6-2 7-6 (9-7).
First seed Stan Wawrinka survived a scare before prevailing against Mikhail Kukushkin to win 4-6 6-3 6-1 in just under two hours.
Wawrinka will take on Alex Bolt in the last 16, while Kyrgios should be tested against fourth seed Borna Coric.
At the Great Ocean Road Open, top seed David Goffin crashed out as world number 146 Carlos Alcaraz celebrated a shock 6-3 6-3 victory.
Karen Khachanov and Jannik Sinner were among the seeds who progressed, both winning without dropping a set.