Andy and Jamie Murray joined forces in the doubles to give Great Britain a 2-1 lead in their Davis Cup first-round tie against Japan in Birmingham.
The Scottish brothers beat Yoshihito Nishioka and Yasutaka Uchiyama 6-3 6-2 6-4 to leave the holders one win from a quarter-final place.
Andy Murray will hope to secure victory when he faces Kei Nishikori on Sunday.
Nishikori, the world number six, was rested for Saturday’s doubles after beating Dan Evans on Friday.
Evans, ranked 157th, would line up against world number 87 Taro Daniel if a decisive fifth rubber were required.
Captain Leon Smith’s decision to play Andy Murray in the doubles resulted in a one-sided win, but it will only be fully vindicated if the British number one can overcome Nishikori on Sunday.
“I know who I’d want going out for my team – it’s Andy,” Smith told BBC Sport. “It’s going to be difficult, Kei’s a really good player.”
Murrays make short work of doubles
The British brothers did not face a single break point as they saw off Nishioka and Uchiyama in one hour and 53 minutes, taking their Davis Cup record as a doubles team to 5-0.
There was little tension for the majority of the 9,000 crowd to endure as the home side overcame some solid early resistance to dominate.
Both Japanese players are ranked outside the world’s top 300 in doubles, in stark contrast to the world number two singles and doubles players across the net.
It was singles star Andy Murray who made the initial breakthrough with a return winner for a 5-3 lead and it was one-way traffic from then on.
Two breaks of serve in the second set left Japan with a mighty task but they held their own in a tight third before Britain broke through at 4-4, Andy Murray sealing victory with an ace.
Andy Murray: “We know each other’s games extremely well – so that helps. When the ball goes into a certain part of the court I know what shot he will hit and vice-versa. My strengths and his strengths make a decent team. It was a good win today.”
Jamie Murray: “We played a great match from start to finish. We were very solid, it wasn’t easy because they played some good shots and gave us some tricky moments.”
Order of play:
Andy Murray beats Taro Daniel 6-1 6-3 6-1
Kei Nishikori beats Dan Evans 6-3 7-5 7-6 (7-3)
Andy Murray Jamie Murray beat Yoshihito Nishioka Yasutaka Uchiyama 6-3 6-2 6-4
Sunday reverse singles
Andy Murray v Kei Nishikori
Dan Evans v Taro Daniel
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