Kyle Edmund, once anointed as Andy Murray’s successor and now his late-career understudy, rediscovered his best tennis to tame the combative Mikhail Kukushkin in straight sets and set Great Britain on their way into the Davis Cup quarter-finals, against Germany on Friday.

After Edmund won 6-3, 6-3 in an hour and a quarter on Thursday, Dan Evans took the opening set but could not finish the job and Alexander Bublik levelled the tie for Kazakhstan behind a big serve, winning 5-7, 6-4, 6-1.

Andy Murray hangs tough as Britain beat Netherlands in Davis Cup opener Read more

Jamie Murray and Neal Skupski beat the late doubles substitutes Kukushkin and Bublik (backing up after less than an hour’s break and still wearing one long pink sock), 6-1, 6-4, and the squad breathed more easily.

Jamie Murray said courtside: “We played a great match, start to finish. We didn’t let them settle. Neal did a great job both days, an amazing level of tennis.”

Skupski, making his Davis Cup debut this week, added: “We both put the work in. Got a tough match now against Germany.”

Defeat would have put the 2015 winners out of the new-look competition, marketed as the World Cup of Tennis – and now they must steel themselves for a renewal of a long rivalry with Germany.

Quick guide Davis Cup quarter-finals Show Hide Serbia v Russia

Australia v Canada

Great Britain v Germany

Argentina v Spain

Andy Murray will surely be back on deck after a day’s rest, and will play Philipp Kohlschreiber, whom he has beaten five times out of six, but he will surely never forget being embarrassed by him inside an hour when they first met, on the clay of Monte Carlo in 2010.

Kohlschreiber, who has played well in Madrid, said on Thursday: “He won again recently [in Antwerp] so he is getting back the taste for winning. We all know maybe he’s not what he was before but, mentally, the fighting spirit is still Andy Murray. He’s still very strong. I would love to play against him. It’s going to be a great tennis match. Playing for your country is always very special and we would enjoy it.”

Facebook Twitter Pinterest Jamie Murray and Neal Skupski secured the decisive victory. Photograph: Clive Brunskill/Getty Images for the LTA

Drafted in to replace Murray after the former world No 1 went to the edge of his stamina levels in beating the Dutch clay-courter Tallon Griekspoor on Wednesday over nearly three hours of a match he admitted he did not deserve to win, Edmund played some outstanding tennis.

“For quite a chunk this year, I wasn’t where I wanted to be at [physically] and really battling that,” Edmund said. “But the last few months I’ve felt I can push harder. That’s helped me as my game is to be explosive, powerful.”

Kukushkin saved two break points after 20 minutes but gifted Edmund a third with a double fault, saved it, hit loosely again twice, and surrendered his serve. Edmund had to save two break points for a nervous hold. Kukushkin, one of the feistiest characters on the circuit, held and forced Edmund to serve for the first set. He obliged in commanding fashion to love, with back-to-back aces.

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Edmund, who had lost his only previous match against Kukushkin – after winning the first set on the grass of Eastbourne last year – was aware how dangerous the Kazakh can be when cornered. Also, recovering in body and spirit after eight losses on the spin accelerated his tumble down the rankings from a career-high 14 in January to 69, two adrift of Kukushkin, he needed all his grit to consolidate his lead.

Edmund won 85 % of the first serves that landed, bolstered by 10 aces, and his ramped-up backhand was a second sword of considerable potency alongside his trademark forehand. His commitment was total, his concentration unwavering.

He later identified Jan-Lennard Struff as Germany’s danger man. “I know Struff off the court and he’s a really nice guy,” Edmund said. “The way he plays, he’s just so dangerous. He’s very free, goes for his shots.”

Evans had a much tougher time against the unorthodox Bublik. He broke him in the 12th game to seal the first set, and the emotional right-hander went into a minor rage, destroying his racket, but he cashed in when Evans lost focus in the second set, then found a deadly rhythm in the third.

At the end Evans was nonplussed, his legs as heavy as his heart. Bublik left him standing as he hit winner after winner while sprinkling his game with aces and double faults in a wild charge at the line.

“I’ve had two tough days,” Evans said, looking back on his defeat by the experienced Dutchman Robin Haase, on Wednesday, when he served for the match at 5-4 in the second set. “It’s difficult. I wanted to get a point on the board for the guys. I thought I didn’t do a lot wrong, he just played pretty good.” It mattered not and so it is Germany next, with Spain or Argentina waiting for the winner in the semi-finals.