Glasgow: Andy and Jamie Murray kept Great Britain's hopes of retaining their Davis Cup title alive as they defeated Argentina's Juan Martin del Potro and Leonardo Mayer in four sets in the doubles rubber of their semi-final on Saturday.
Leading 2-0 from Friday's singles, Argentina captain Daniel Orsanic selected Del Potro alongside Mayer instead of his usual partner Federico Delbonis as they looked to wrap up victory early.
However, the tactic backfired as world number two Andy and his older brother Jamie secured a thrilling 6-1, 3-6, 6-4, 6-4 victory in just under three hours on the hard court of the Emirates Arena in Glasgow.
"Yesterday was a very tough day. To come out and get the win with Jamie today was great," three-time Grand Slam winner Andy said.
"He played unbelievably well throughout the whole match. We are 2-1 down and it is a tough position to be in, but it is a better position that we were in at the beginning of the day and I still believe we can come back."
Argentina are looking to reach their fourth final in 10 years but will have to wait until Sunday's reverse singles rubbers to try and claim the point they need for a place in the final against either Croatia or France.
Kyle Edmund looks likely to face Del Potro in the decisive rubber as Great Britain attempt to defend the competition they won in Ghent last year, with Andy Murray favourite to defeat Guido Pella in the first reverse singles on Sunday.
"We played a great match but we had to as those guys are playing really well too," said Jamie Murray.
"I think we should be proud of the way we played and competed from start to finish. We’re back in the tie and gives us some momentum back in the tie going into tomorrow's matches."
With his side losing both of Friday's singles, it was no surprise to see British captain Leon Smith pick Andy alongside Jamie instead of Dan Evans as he opted for the pairing who secured victory in last year's final against Belgium.
However, after his five-hour and seven-minute epic win against Murray on Friday, the expectation was that Del Potro, still working his way back into the game following wrist surgery, would take the day off ahead of Sunday's reverse singles.
The gamble to pick the 27-year-old didn't look like paying off with the Argentine pairing initially looking like strangers on the court.
"I felt tired but that is normal. I think for the team it was the best option to play the doubles," Del Potro said.
"I think we did really well. We had some chances but we couldn't win."
It was Jamie, who claimed Grand Slam glory in both the Australian and US Open doubles finals this year, and younger sibling Andy, showing no signs of fatigue, that looked more comfortable in the doubles environment as they helped the Brits race into a five-game lead without reply in the first set before claiming it 6-1 in just 26 minutes.
Their good work seemed to come undone in the second game of the following set as Argentina immediately broke to take a 4-1 lead before serving out to take the set 6-3.
The third set went with serve until the seventh game when Argentina moved in front with a break as Andy struggled with his first serve.
Argentina's joy was short-lived, however, as Britain broke back immediately as they won three games in a row with a clever return down the line from Jamie sealing the set.
There was nothing to separate the sides in the fourth set which went with serve until the tenth game where, in a repeat of the third, the Murrays broke at the crucial moment to claim victory.