Wimbledon champion Novak Djokovic suffered a rare defeat when he and Serb doubles partner Nenad Zimonjic lost 6-4, 7-6, (7/5) 7-5 to Simon Aspelin and Robert Lindstedt as Sweden hit back in the Davis Cup quarter-finals.
World number one Djokovic, beaten just once in singles all year, missed Friday's first day of the tie in Halmstad with a knee injury as defending champions Serbia opened up a 2-0 lead.
And he was unable to repeat the magic which has taken him to the top of the world rankings, as well as eight titles in 2011, as seven-time Davis Cup winners Sweden clung onto their outside hopes of making the semi-finals.
"I expected myself to adjust a little bit better in the rhythm of the return. One of my main weapons wasn't working well as I was missing a lot of returns but that's because of their serves as well, which were great," said Djokovic.
"But we are coming into the third day 2-1 up which is the most important thing and tomorrow we will try to end this tie," he added.
On Friday, Serbia had taken control with world number 16 Viktor Troicki beating Michael Ryderstedt 6-3, 6-1, 6-7 (6/8), 7-5 in the first singles rubber.
World number 29 Janko Tipsarevic then stepped in for Djokovic and enjoyed a comfortable afternoon when debutant Ervin Eleskovic, the world number 355, retired with a knee injury after the Serb had established a 6-2, 1-0 lead.
The winners of the tie will face Argentina in September's semi-finals.
In Buenos Aires, Argentina completed a 5-0 rout of Kazakhstan when Juan Ignacio Chela defeated Evgeny Korolev 2-6, 6-2, 6-0 and Juan Monaco cruised past Mikhail Kukushkin 6-4, 6-1.
The South Americans had already wrapped up the tie on Friday when Chela and Eduardo Schwank saw off Yuriy Schukin and Korolev 6-3, 6-2, 7-5.
Monaco defeated Andrey Golubev 6-3, 6-0, 6-4 and former US Open champion Juan Martin Del Potro beat Mikhail Kukushkin 6-2, 6-1, 6-2 in Thursday's opening singles of a tie brought forward by a day to avoid a clash with elections in the city on Sunday.
Nine-time champions France also made the semi-finals when Michael Llodra and Jo-Wilfried Tsonga overcame Germany's Philipp Petzschner and Christopher Kas 7-6 (7/4), 6-4, 6-4 in Stuttgart.
On Friday, Richard Gasquet came from two sets down to beat German number one Florian Mayer 4-6, 4-6, 7-5, 6-3, 6-3 before Gael Monfils beat Philipp Kohlschreiber 7-6, (7/3), 7-6 (7/5), 6-4.
The French will now face either the United States or Spain in September.
If it is Spain, then the French will have to travel, but any clash against the US would hand Guy Forget's team home advantage.
"Whoever we face in the semi-final will be a big task," said Llodra. "We'd prefer to face the United States at home," he added.
In Austin, Texas, Wimbledon doubles champions Bob and Mike Bryan clinched a 6-7 (3/7), 6-4, 6-4, 6-4 win over Marcel Granollers and Fernando Verdasco to cut the deficit on Spain to 2-1. The Bryan twins took their Davis Cup record to 18-2.
Spain, chasing their third trophy in four years, had finished Friday's opening day 2-0 ahead after world number six David Ferrer defeated 10th-ranked hometown star Andy Roddick 7-6 (11/9), 7-5, 6-3.
Spain, playing without the resting Rafael Nadal, had seized the lead in the opening singles when Feliciano Lopez outlasted eighth-ranked Mardy Fish in a four-hour showdown 6-4, 3-6, 6-3, 6-7 (2/7), 8-6.