Team Russia look set to progress to the semi-finals of the ATP Cup while Canada have notched their first win of the tournament.
Daniil Medvedev was at his clinical best against Alex de Minaur on Tuesday night.
The World No. 2 showed no ill-effects from his taxing encounter with Ugo Humbert and dispatched the Australian 6-4, 6-1 in an hour and 19 minutes.
Medvedev was on fire from the outset with two breaks and a service hold all coming before his first error.
The tie-clinching win came despite the reigning US Open Champion’s post-match admission that he is still battling to be fully fit.
“We fight when we play for our country, to the last point,” Medvedev said. “I didn’t feel great prior to the match, so I took some pain killers before I came out.”
Earlier, Roman Safiullin was an impressive winner over World No. 47 James Duckworth 7-6(6), 6-4 in close to two hours.
Safiullin clawed his way back from 5-2 down in the first set to ultimately secure a lead that he would not squander.
The Russian remains undefeated at this year’s ATP Cup following his win over Frenchman Arthur Rinderknech on Sunday.
"It was a great match for me and the match before as well,” Safiullin said post-match. “This one I would say started more or less the same, but then [I was able to] come back in the first set.”
Later, Medvedev and Safiullin combined for a 7-6(7), 3-6, [10-5] win over the Australian pairing of John Peers and Luke Saville
While the doubles rubber would not decide the victor of the tie, it may still have a bearing on who ultimately progresses from Group D.
Meanwhile over on Ken Rosewall Arena the tie between Canada and Great Britain was locked at 1-1 after Dan Evans and Felix Auger-Aliassime secured straight-set wins.
World No. 25 Evans maintained his perfect start to the season with a 6-4, 6-4 win over Denis Shapovalov in an hour and 22 minutes.
The 31-year-old did not face a break point but found himself able to put pressure on his opponent's service games by remaining patient and drawing errors.
Post-match, Evans attributed his level of play to the chance to play events like the ATP Cup.
"I love representing my country," Evans said in his on-court interview. "It is the best thing you can do in any sport in my opinion.
World No. 11 Auger-Aliassime was another impressive winner on the night. He overcame Cam Norrie 7-6(4), 6-3 in just under two hours.
The Canadian was able to pin his opponent well behind the baseline for much of the match thanks to heavy groundstrokes that allowed him to notch 18-winners in the first set alone.
In his on-court interview after the match, Auger-Aliassime made it clear that his job was not yet over.
“Stepping onto court against a player like Cam, who plays really well, you try to find a way to win and the most important thing at the end of the day is the victory. I am happy to keep the team alive, but the work is not done.”
The deciding doubles rubber saw Shapovalov and Auger-Aliassime return to court to face the experienced duo of Jamie Murray and Joe Salisbury.
The first set looked to be headed for a tiebreak before the Canadian pair managed to breakthrough at 5-4.
The match and tie quickly unravelled for Team Great Britain with Shapovalov and Auger-Aliassime serving well and returning with strong depth to run away 6-4, 6-1 winners.
The result means all four Group C teams hold a 1-1 record going into the final ties on Thursday.
In ATP Cup action on Wednesday, Norway and Chile face off in the day session at Ken Rosewall Arena before Serbia meets Group A leaders Spain.
Over at Qudos Bank Arena, Poland and Argentina will open proceedings with the winner of that tie to progress to the semi-finals. Greece will take on Georgia in the night session.