Great Britain's Cameron Norrie produced a stunning comeback on Friday to beat Spain's Roberto Bautista Agut in the Davis Cup.
With Spain 1-0 ahead after the first rubber, they appeared on course to end the day in complete control of their tie against Great Britain. But Norrie, ranked 114th in the world, accomplished a sensational fightback to get the better of the world No. 23: 4-6, 3-6, 6-3, 6-2, 6-2.
Elsewhere, defending champions France are deadlocked with the Netherlands after Friday, while second seeds Belgium are dominating against Hungary. The United States also lead 2-0 in Serbia.
Here's how things stand after Friday's matches and a look back at some of the highlights from the World Group of this unique competition.
(1) France 1-1 Netherlands
Japan 1-1 (8) Italy
Spain 1-1 (3) Great Britain
(6) Australia 1-1 Germany
Kazakhstan 2-0 (5) Switzerland
(4) Croatia 1-1 Canada
(7) Serbia 0-2 United States
(2) Belgium 2-0 Hungary
For Saturday's schedule in full visit the competition website.
After Albert Ramos-Vinolas breezed past Liam Broady to give Spain an early advantage in Marbella, Great Britain's hopes appeared to be hanging by a thread with Norrie in a hole against Agut.
So for him to find some incredible form and storm back into the contest was a remarkable achievement, all things considered. The 22-year-old showcased a potential that far exceeds his current ranking.
Indeed, after putting together his comeback, three-time Grand Slam champion Andy Murray was full of praise for the youngster:
James Gheerbrant of the Times complimented the role of captain Leon Smith getting the best out of the players on his team:
Indeed, should Great Britain go on to make a deep run into this year's competition, this win from Norrie could be deemed a pivotal moment. But they still have a lot of work to do over the weekend if they're to edge past a talented Spain squad.
There are a number of tantalisingly poised ties ahead of the final two days, with France facing a battle as they seek to defend their title.
In the first match, Thiemo de Bakker turned in an excellent display to beat France's Adrian Mannarino in straight sets. It heaped the pressure on the experienced Richard Gasquet in the second match and he eventually got past Robin Haase in four.
As we can see courtesy of doublefault28, there were some wonderful moments from the Frenchman during his win:
One of the few teams in a dominant position is Belgium, who will be desperate to clinch their maiden Davis Cup title after runners-up finishes in two of the last three editions. Wins for Ruben Bemelmans and David Goffin showed they mean business.
One of the best matches of the day came between Germany's world No. 4 Alex Zverev and Australian's 18-year-old Alex de Minaur, who is ranked 135 places below opponent.
Zverev eventually grabbed the win after five thrilling sets. The Davis Cup Twitter account captured the contrast in emotions between the two players:
The last match to finish on Friday was between the United States and Serbia, with Sam Querrey and John Isner teaming up for the 32-time winners of the prize.
Querrey eventually got past Laslo Djere in four sets to give the visitors an important lead, while Isner outlasted Dusan Lajovic over five sets.