With Andy Murray in an observer capacity in Belgrade, Kyle Edmund was Britain’s hero as the 21-year-old won both his singles rubbers to earn the defending champions a 3-2 victory at the Tasmajdan Stadium.
Next up is a home tie against Argentina in September where, with Murray having already said he is planning to take part, Britain would be favourites to advance to the final for the second year in a row.
November’s victory over Belgium earned Britain a first Davis Cup title since 1936 and a repeat now looks a distinct possibility.
Captain Smith, whose impressive record improved to 14 wins from 16 matches, said: “We absolutely love Davis Cup, they’re amazing weekends. We love our home ties, we have so much fun together as a team.
“It’s great to showcase our sport again, especially later in the year after our grass season has finished and we’ve got this huge event now.
“The journey keeps going and we’re enjoying it as much as the first tie we had as a team together, and we just want to keep going.”
A venue for the semi-final will be announced in due course but it is very likely to be Glasgow. Scotland has not staged a tie yet this season while Murray is hosting a charity event at the Hydro only three days after the tie on 16-18 September.
Argentina defeated Italy to book their place in the last four, with a key factor being the return to their team of former US Open champion Juan Martin del Potro, who was sidelined for two years by wrist problems.
But their highest-ranked player is Federico Delbonis at 43 and, with Edmund having proved his ability to win key rubbers at World Group level and Britain boasting a superb record in doubles, there are few chinks in Smith’s side’s armour.
The captain said: “Argentina have got good depth, a lot of good players. Del Potro coming back obviously is big for them, so we’ll see how the rest of the summer goes for him because he’s obviously their most dangerous player.
“It’s going to be difficult but we are also a very good team. We see what Kyle’s done this weekend, Andy when he comes back in, Jamie [Murray] in the doubles, Dom [Inglot] in the doubles, we’ve got good back-up as well when needed.”
At 21, Edmund is one of the leading young players in the world and showed great maturity in taking the No 1 role in Davis Cup for the first time in only his second tie and delivering for his country.
The Yorkshireman did not drop a set in two matches and, although he wobbled in sight of the finish line in what proved to be the decisive rubber against Dusan Lajovic on Sunday, he regained his composure and dominated with his heavy forehand.
There is no rest for Edmund, who heads to Toronto today to play in qualifying for the Rogers Cup – which Murray looks set to miss – before making his Olympic debut in Rio.
It would be a surprise if his coming-of-age weekend did not have a positive impact, with Edmund saying: “These matches give you confidence.
“Different situations give you confidence. Knowing that you are able to keep your level in those situations.
“I’ve known that I’ve been improving, but on the match court is where you want it to count. There’s no point playing well in practice and then when you come to matches you don’t quite get it out there. It’s nice to be able to execute that.
“At the same time, there will be stuff that I feel I could have done better here. You are always trying to find that extra one or two per cent to make you better. It never stops. People don’t stop working. I certainly don’t.
“I will look to improve and take this experience and enjoy it. There are a lot of times you come off court and you’re a bit down on yourself because you feel the other guy played better. So you enjoy it and move on and get better.”