Britain reached the Davis Cup final for the first time in 37 years as Andy Murray outclassed Australia's Bernard Tomic in straight sets to give them an unbeatable 3-1 lead.
World number three Murray had teamed up with brother Jamie to win a thrilling five-set doubles rubber against Lleyton Hewitt and Sam Groth on Saturday to leave the hosts needing to win just one of Sunday's reverse singles.
The 28-year-old, who became the first Briton to win the Wimbledon men's singles in 77 years in 2013, duly delivered his third point of the match, beating an increasingly dispirited Tomic 7-5 6-3 6-2 to wild cheers from a partisan Glasgow crowd.
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In doing so, Murray improved his record in Davis Cup singles to 25-2 - an incredible contribution and the main reason Britain have risen from the depths of the competition in 2010 to within one victory of their first title since 1936.
"Obviously, winning for your country and your team mates means a lot. The crowd were unbelievable from the first ball to the last," Murray told the BBC.
"I didn't feel great the whole weekend to be honest, I've been struggling with my back, but I just tried to disguise it. We've got everyone here, mother, father, wife, grandmother, mother-in-law, aunties and uncles."
After that the outcome of the match became a formality as a clearly tired Murray managed to dominate, setting up a final against either Belgium or Argentina.
That semi-final was locked at 2-2 in Brussels with the final singles rubber still to be played.
Meanwhile, Roger Federer guided Switzerland to victory in their Davis Cup World Group playoff tie against the Netherlands with an easy 6-3 6-2 6-4 victory over Thiemo de Bakker.
|Federer had lost the US Open final to Djokovic a week ago [EPA]
The 17-time grand slam champion, beaten by Novak Djokovic in the US Open final a week ago, recovered after losing Saturday's doubles with Marco Chiudinelli to give the Swiss a decisive 3-1 lead and secure their World Group spot.
Switzerland, winners last year, were beaten by Belgium in the opening round in March when neither Federer nor Stan Wawrinka lined up for the Swiss.
In other playoff ties, the Czech Republic clinched victory against India in New Delhi, while the United States secured a winning 3-1 lead in Uzbekistan thanks to victory for Jack Sock against Denis Istomin.