Serbia's Viktor Troicki defeated Belgium's David Goffin in a Davis Cup five-set thriller on Friday, mastering a clay court condemned as dangerous by world number one compatriot Novak Djokovic.
Troicki battled back from two sets down in Charleroi to win 1-6, 3-6, 7-6 (7/5), 6-4, 6-4, paving the way for newly-crowned Australian Open champion Djokovic, who skipped the Davis Cup in 2012, to face Olivier Rochus in the second rubber.
Djokovic goes into his clash having lashed out at the clay court at the Spiroudome de Charleroi which was laid on top of parquet floor.
"It's the worst court I have ever played on. It's very, very dangerous," raged Djokovic after training on Thursday.
But the International Tennis Federation claimed on Friday that referee Remy Azemar had inspected the court and confirmed that it was of a playable condition.
"There has been some speculation that laying the temporary clay court surface on wood was a source of the problem but the ITF has approved many temporary clay courts laid on wood including more than twelve since 2009 that have been laid without issue," said an ITF statement.
"The ITF would like to thank the Federation Royale Belge de Tennis for their response to our requests and their efforts over the last 24 hours to ensure that the court is fit for play."
Serbia, the 2010 champions, are looking to reach the World Group quarter-finals for a fourth consecutive year, while Belgium are hoping to make the next stage for the first time since 2007.
France put one foot in the quarter-finals when they took a 2-0 lead over Israel in Rouen in a tie which represented Arnaud Clement's debut as national coach.
Jo-Wilfried Tsonga, the world number eight, beat 173-ranked Amir Weintraub 6-3, 6-3, 4-6, 7-5 before world number 10 Richard Gasquet breezed past Dudi Sela, ranked at 106, in straight sets, 6-3, 6-2, 6-2.
Michael Llodra and Julien Benneteau can wrap up the tie in the doubles on Saturday if they beat Sela and Jonathan Erlich.
Defending champions Czech Republic finished the day in Geneva at 1-1 against Switzerland.
Stanislas Wawrinka, the Swiss team's number one in the absence of Roger Federer, saw off Lukas Rosol, the shock conqueror of Rafael Nadal at Wimbledon last year, 6-4, 6-3, 6-4.
World number six Tomas Berdych then defeated Finland-born Henri Laaksonen, the world 289, 6-3, 6-2, 6-7 (5/7), 6-1.
The winners of that tie will meet either Kazakhstan or Austria in the last eight.
Kazakhstan led 2-0 after the opening day in Astana with Andrey Golubev beating Andreas Haider-Maurer 7-6 (7/2), 6-3, 7-6 (7/5) and Evgeny Korolov seeing off the experienced Jurgen Melzer 7-6 (7/4), 6-3, 6-2.
Later Friday, Spain, winners three times in the last five years, and runners-up to the Czechs in 2012, travel to Vancouver to face Canada without their three top players -- the injured Rafael Nadal and Nicolas Almagro and the resting David Ferrer.
Canada's top player is big-serving Milos Raonic, who stands at 15 in the world while, in the shape of Daniel Nestor, they boast one of the world's most accomplished doubles players.
The winner of that tie will face either Italy or Croatia in the quarter-finals.
Marin Cilic gave Croatia a 1-0 lead in Turin with a marathon 6-1, 6-7 (6/8), 4-6, 6-3, 6-2 win over Paolo Lorenzi who had replaced Fabio Fognini who was suffering from flu.
The United States, the 32-time champions, will face Brazil in Jacksonville where the winners will face either Belgium or Serbia.
Argentina, who have lost all the three finals in which they have appeared, welcome Germany to Buenos Aires with a last-eight clash with either France or Israel on the cards.