SYDNEY, Jan 4 (Reuters) - World number two Daniil Medvedev produced a dominant performance to overwhelm Australia"s Alex de Minaur and help Russia go within touching distance of the ATP Cup semi-finals, while Germany and Italy also scored victories in Sydney on Tuesday. Medvedev"s flawless display in his 6-4 6-2 victory was the perfect response to his stunning defeat by France"s Ugo Humbert on Sunday and wiped out any doubts about his readiness for this month"s Australian Open. After Roman Safiullin battled past James Duckworth 7-6(6) 6-4 to give Russia a 1-0 lead, Medvedev turned on the style to race through the opening set against De Minaur before racing ahead 5-0 in the second and clinching the tie. "We fight when we play for our country, to the last point. I didn"t feel great prior to the match, so I took some pain killers before I came out," Medvedev said. "I"m really happy for Roman, he"s winning every match he"s played so far. I watched his match tonight from the locker room. I"ve known him since he was 10, he had a good junior career and has been unlucky with injuries. The U.S. Open champion returned for the doubles, combining with Safiullin to outlast John Peers and Luke Saville 7-6(7) 3-6 10-6 in an absorbing encounter where the Aussie pair were left to rue a missed set-point opportunity in the opening set. In Group C, Felix Auger-Aliassime was the catalyst for Canada as he impressed in both the singles and doubles decider to lead them to victory over Britain. Dan Evans had put Britain in control with a 6-4 6-4 victory over Denis Shapovalov but Auger-Aliassime levelled the tie after edging past Cameron Norrie. Auger-Aliassime, the world number 11, closed out a 70-minute opening set after winning the tiebreaker and broke Norrie twice in the second set to hand Canada their first ATP Cup victory and force the deciding doubles match. "I am happy with the win," Auger-Aliassime said. "I am happy to keep the team alive, but the work is not done." The 21-year-old teamed up with Shapovalov to complete the comeback, making light work of Joe Salisbury and Jamie Murray in a 6-4 6-1 win. Earlier, world number three Alexander Zverev topped American Taylor Fritz 6-4 6-4 to keep alive Germany"s ATP Cup semi-final hopes, while Matteo Berrettini powered Italy to a 3-0 victory against France. After Jan-Lennard Struff survived a 34-ace onslaught from John Isner to prevail 7-6(7) 4-6 7-5, Zverev broke Fritz early in both sets and capitalised on a sixth match point to secure victory in the Group C tie. The win moved Germany, who lost to Britain in their opener, to 1-1 in the group before they face Canada on Thursday. "Until the last game it was a good level for my second match of year. It was very intense and hard hitting," said Zverev, who will be gunning for glory at the Jan. 17-30 Australian Open. "The most important thing is that team Germany won and we gave ourselves the best chance to qualify for the semis." World number seven Berrettini saw off Humbert 6-4 7-6(6) in Group B after Jannik Sinner had defeated Arthur Rinderknech 6-3 7-6(3). Following his success over Medvedev, Humbert had threatened another upset after forcing a tiebreak in the second set, but Berrettini dominated with his serve to clinch the tie for Italy. "It was a really tough match especially in these conditions. He"s a great server, a tricky player," said Berrettini.