Tommy Haas helped to keep Germany in the hunt for a place in the World Team Cup final as they beat Sweden 2-1 on Wednesday.
The German number one beat Sweden's Joachim Johansson 6-0, 3-6, 6-3 before joining forces with Alexander Waske for a 6-4, 6-4 doubles win over Jonas Bjorkman and Johansson to give a jubilant host nation the decisive point.
Their showdown with Spain on Friday will decide the finalist from the Blue Group. The Spaniards also chalked up their second series victory of the tournament with a 2-1 win over a second-string United States team.
Thomas Johansson had earlier kept Sweden's slim chances of reaching the final alive with a defiant 6-4, 6-2 win over Nicolas Kiefer, which left the countries level at 1-1 heading into the doubles rubber.
Joachim Johansson missed Monday's 2-1 defeat by Spain with a hamstring strain and was caught flat-footed during Wednesday's opening singles encounter as Haas stormed through the first set without dropping a game.
Although the Swede eventually dug his heels in at the Rochusclub's centre court to make a comeback in the second set, Haas made the most of the home support to clinch victory.
"After such an opening set you know that your opponent has to change something especially since he is such a dangerous player," said Haas.
"I just tried to concentrate on my game and thank God it worked out."
Germany, who beat the United States on the opening day of the eight-nation tournament, could have sealed Sweden's fate had Kiefer won.
Instead, former Australian Open champion Thomas Johansson showed his resilience and silenced the partisan crowd with an efficient performance against Kiefer.
CLAYCOURT EXPERTISE
The cheering fans were back on their feet, though, when Waske's backhand shot hurtled past the outstretched rackets of the Swedish doubles pair to seal the 2-1 result.
Spain's Tommy Robredo displayed his greater claycourt expertise in dispatching American Vince Spadea 6-3, 2-6, 6-3.
With the Americans having to do without the services of Andy Roddick and former French Open champion Andre Agassi, it was never going to be an easy task for the four-time champions to reclaim the title they last won in 1993.
Jeff Morrison's 6-4, 7-6 defeat by David Ferrer in the second singles left the US with no chance of making the final.
Twice champions Chile and title favourites Argentina meet on Thursday to decide the finalists from the Red Group.
The eight countries play in two round-robin groups of four teams. The top nation in each group progresses to the final.
At the Istanbul Cup, former world number one Venus Williams will look to build up her confidence ahead of the French Open against Russia's Anna Chakvetadze in Thursday's quarter-finals.
The American would have been encouraged by her 6-0, 6-0 whitewash over Spaniard Marta Marrero on Tuesday and will want to continue in similar fashion as she aims to win her first title since her success in Warsaw last May.
