Daniil Medvedev has added to the star power heading to Sydney for the ATP Cup finals after sealing Russia's place in the last eight of the inaugural $22 million teams' event.
Russia joined Australia and the Novak Djokovic-led Serbia in the quarter-finals after completing a clean sweep of their pool matches with a 3-0 win over Norway that ultimately decided Group D.
Runner-up to Rafael Nadal at last season's US Open amid a stunning run of six straight hard-court finals, Medvedev clinched victory for Russia with a 6-3 7-6 (8-6) win over Casper Ruud in Tuesday's opening singles match in Perth.
Karen Khachanov had earlier routed Victor Durasovic 6-2 6-1 to give Russia a 1-0 lead at RAC Arena.
The fifth-ranked Medvedev will join seven-times Australian Open champion Djokovic, Lleyton Hewitt's Australian team and almost certainly world No.1 Rafael Nadal in Sydney for the knockout stages starting on Thursday.
Only an improbable 3-0 drubbing at the hands of Japan on Wednesday can stop Nadal and his Spanish Davis Cup-winning teammates from making the quarters.
Great Britain kept their finals hopes alive with a 3-0 defeat of Moldova.
British No.1 Dan Evans outclassed Radu Albot 6-2 6-2 to clinch the tie after Cameron Norrie beat Alexander Cozbinov by the same scoreline.
A 6-2 6-3 doubles victory for Jamie Murray and Joe Salisbury over Albot and Cozbinov completed an important whitewash, leaving the Brits in the box seat to also qualify.
Britain could yet still top Group C and face Australia in Thursday's first quarter-final at Sydney Olympic Park.
But Tim Henman's men are more likely to advance as one of the two best pool runners-up at the season-opening six-group competition.
Unbeaten in their first two ties, Bulgaria remain favourites to top Group C and can secure a quarter-final spot with success over Belgium on Tuesday night.
Australia, already assured of topping Group F, wrap up their pool campaign on Tuesday night in Brisbane.
Hewitt opted to rest undefeated singles spearhead Alex de Minaur against out-of-contention Greece.
In Tuesday's opening tie in Brisbane, Canada eliminated Germany with a 2-1 victory that completed a disastrous Australian Open preparation for Alexander Zverev.
Zverev coughed up another seven double-faults in a 6-2 6-2 loss to Denis Shapovalov, taking the world No.7's tally for his winless week to 31 doubles in 31 service games.
Jan-Lennard Struff had put Germany up 1-0 with a 6-1 6-4 defeat of Felix Auger-Aliassime.
But Zverev's loss and a 6-3 7-6 (7-4) doubles win for Shapovalov and Auger-Aliassime over Kevin Krawietz and Andreas Mies sealed Germany's fate.
With a 2-1 record, Canada can still scrape into the quarter-finals as one of the best two group runners-up, but Germany (1-2) have no hope.