PARIS (AFP) - Novak Djokovic and Andy Murray spent almost 10 hours on court between them on Sunday as they steered Serbia and Britain into a blockbuster Davis Cup quarter-final showdown.
World No. 1 Djokovic needed 4hr 57min to defeat Mikhail Kukushkin 6-7 (6-8), 7-6 (7-3), 4-6, 6-3, 6-2 to pull Serbia level at 2-2 with Kazakhstan in Belgrade.
Viktor Troicki then beat world No. 200 Aleksandr Nedovyesov 6-2, 6-3, 6-4 to put 2010 champions Serbia into a July 15-17 quarter-final with defending champions Britain.
Djokovic hit 19 aces and 37 winners but committed 94 unforced errors in his epic win over Kukushkin.
"This was one of the most difficult matches in my career both physically and mentally," said 28-year-old Djokovic, who again was feeling the effects of a shoulder twinge.
World No. 2 Murray needed 4hr 55min in Birmingham to defeat Kei Nishikori 7-5, 7-6 (8-6), 3-6, 4-6, 6-3 in another epic duel as his side took an unbeatable 3-1 lead over Japan.
Murray had seemed set for a comfortable afternoon against sixth-ranked Nishikori by taking the first two sets against a player he had defeated five times in six previous encounters. But Nishikori battled and was even a break to the good in the deciding set before Murray stormed back for victory.
"The crowd helped for sure. I was struggling a little at the end of the third and a little bit throughout the fourth," said Murray, who had been looking at the prospect of losing from two sets up for the first time in 11 years.
"There were long rallies, he was pushing me quite far off the baseline. I was trying to keep the points short but in the fifth I had to grit my teeth, fight hard and I managed to get the win."
Murray, 28, was playing for the first time in five weeks after taking time off to be with wife Kim and baby daughter Sophia.
In Melbourne, record 32-time winners United States wrapped up a 3-1 win over Australia but the result was overshadowed by a bitter row between fiery Aussie teammates Bernard Tomic and Nick Kyrgios.
Tomic challenged the commitment of Kyrgios to the Davis Cup after his team-mate's withdrawal from the Kooyong tie with illness and back trouble.
John Isner was too strong for Tomic, winning 6-4, 6-4, 5-7, 7-6 (7-4) to deliver the Americans a quarter-final clash against Croatia.
Yet there was controversy during the match when Tomic was overheard during a changeover questioning Kyrgios's absence from the tie.
While in conversation with team captain Lleyton Hewitt, television microphones caught Tomic muttering: "Nick's sitting down in Canberra. Bulls***t he's sick." Tomic was also heard saying "that's twice he's done it", in possible reference to Kyrgios's withdrawal from the tie against the Czech Republic last year.