THE Davis Cup is criticised for a failure to provide genuine world class match-ups but on Mother's Day one new dad from Scotland found himself embroiled in the mother of all battles. Watched by his mum Judy, not to mention her mum Shirley - while his wife Kim tended three-week old Sophia back in their Surrey home - Andy Murray produced a paternity-busting performance to demoralise Kei Nishikori, the World No 6 from Japan, by a 7-5, 7-6 (6), 3-6, 4-6, 6-3 scoreline in just shy of five gruelling hours at the Barclaycard Arena.

This was the highest-ranked player he had ever faced in this competition, his victory clinching Britain's quarter final place and extending his personal winning streak in this competition in both singles and doubles to 14 wins This was enough to smash Fred Perry's all-time record and prove yet again that in British terms at least he is the Davis Cup daddy of them all.

At times during this match, though, the Scot must have felt more like crying like a baby. He has lost just one match in his career from two sets to the good - to David Nalbandian at Wimbledon in 2005. He was just a child back then, rather than just having had one of his own, but the thought of history repeating itself must have been coursing through his mind when he marched off court to take a toilet break and compose himself for the deciding set.

Whilst Britain would still have had hopes of clinching the tie via a deciding rubber between Birmingham's Dan Evans and Taro Daniel in any case, that wasn't the point. It all felt a bit like the 2012 US Open final, where having just been pegged back by Novak Djokovic, Murray issued himself a stern talking to in the mirror before refusing to succumb to his fates. Incidentally, that match now shares equal billing with this one for the longest of his entire career and Djokovic now waits to contest an even more momentous Davis Cup quarter final showdown, having required three minutes longer than Murray did to take care of Mikhail Kukushkin of Kazakhstan. It will be the first-ever match-up in this competition between members of the so-called 'big four' of men's tennis.

Like many young dads, Andy had a concerned look on his face for much of the afternoon. Rather than the triumphant noise of the Proclaimers or Deacon Blue, the day's soundtrack was becoming the shrieks from the teenage Japanese girls sitting courtside which greeted each Nishikori winner, punctuated by grunts of Scottish anguish.

A match of gruelling, lengthy rallies and incredible shot-making under duress, second guessing who was going to win each point was hard enough, let alone who would prevail. Murray had won five of his six previous meetings with Nishikori, with the only defeat coming indoors, on the Scot's 'home' soil at the ATP Tour finals but the World No 6 sat with his feet up on Saturday, while Andy partnered his brother Jamie in the doubles. While Murray has still not lost a Davis Cup singles tie on a hard court, Nishikori had won his last 11 singles rubbers too.

The opening two sets belonged to Murray but they were still fraught with difficulty. There were nerves even during the knock-up, and first serve which has appeared so solid this weekend went missing early on - so disgusted was he by it that the Scot bellowed 'b***** off" after one errant delivery into the net - and a balloon which burst mid-point didn't help. Four break points had to be saved in various games before Nishikori swatted a backhand down the line and this set was back in the balance at 4-3.

Murray's inspired returning had given him an early advantage, but this set had become a matter of who would blink first and the answer was Nishikori. Serving 5-6 down, he double faulted twice and Murray eventually got him, down the line, the Scot left waving a fist, Andy Halliday-style, at the crowd.

It was Nishikori's turn for a toilet break, returning refreshed enough to break to 15. While Murray earned a warning for racket abuse when he smashed it off his own shoes in disgust, he used the new one to produce some of his best tennis, a sweet backhand down the line restoring second set parity at 2-2.

If the Scot's state of mind was improving, that was challenged somewhat during the next game. Both players were towelling down and taking a drink when a late challenge from Nishikori forced Murray to save another break point before sitting down at 4-3.

It summed up an afternoon where nothing came easy. Two set points came and went at 5-6, then from 4-love up in the tie-break suddenly the Scot was 5-4 down. He had a set point to save before an inch-perfect defensive lob changed the momentum in his favour. But his Japanese opponent was far from finished.

As much as Murray's physical condition deteriorated during sets three and four, Nishikori deserves huge credit for capitalising on his ragged opponent. The World No 2 appeared to have regathered himself by the end of the fourth, but a double break down, he had left himself too much to do. Three straight service breaks tilted the decider in Murray's favour but the anarchy only came to an end when Murray grimly held for 5-2.

Two match points came and went but three more soon arrived and there was to be no stopping the Scot from recording the most remarkable Davis Cup win of his career. So far anyway. He had hoped to get back to help Kim out with little Sophia's Mother's Day bath time, but plunging his weary body in a celebratory ice bath probably felt like more of a priority last night.