Novak Djokovic and Andy Murray's French Open final hopes were on a knife edge on Friday after a thunderstorm left the pair facing an uneasy night wondering who will face Swiss Stan Wawrinka in Sunday's showpiece contest.
A battle between the Serbian and British heavyweights had promised much, got off to bit of a false start but was then building towards a rousing finale when an approaching storm brought a halt to proceedings at Roland Garros.
The duo were sent scuttling back into the locker room with world number one Djokovic leading 6-3 6-3 5-7 3-3
One man who will not be feeling sorry for them is eighth seed Wawrinka.
The 30-year-old will be delighted to get a whole day's rest after he outlasted home hope Jo-Wilfried Tsonga 6-3 6-7(1) 7-6(3) 6-4 in a gruelling three hour 46 minute tussle under blazing sunshine with the mercury hitting 33 degrees Celsius.
The suffocating heat even left the players dazed and confused midway through the fourth set, with Tsonga slumping on his seat after four games when there should have been no break or changeover.
Chants of "Tson-ga, Tson-ga, Tson-ga" failed to rouse the crowd favourite who was bidding to become the first Frenchman to reach the final since Henri Leconte in 1988.
Wawrinka, clearly able to deal with the intense heat better, fired an unreturnable serve to complete a remarkable turnaround in his fortunes. A year after losing in the first round, the Swiss will play for the ultimate prize in claycourt tennis.
"Today it was a tough battle. Jo is always a tough player to play, especially when he's playing at home here in Paris," said Wawrinka, who saved 16 of the 17 break points he faced.
"The match could have gone his way also when he had so many chances to take advantage in the third set.
"Really happy and proud of the way I stayed mentally. When I play my best, I know I can beat all the players."
Wawrinka has already proved he can by overcoming Rafa Nadal to win the 2014 Australian Open and trumping 17-times grand slam champion Roger Federer in the quarter-finals here.
All that remains is to see which of the remaining members of the Big Four the Swiss faces in the final.
For the first 90 minutes of the Djokovic-Murray semi-final, that man had looked to be the Serbian world number one.
When 2013 Wimbledon champion Murray surrendered the second set with a smash that was so wild and so long, he might as well have been aiming for the Eiffel Tower 5km away.
But just when it seemed Djokovic was on the verge of wrapping up his 18th successive set at this year's championships, with the third set locked at 5-5, Murray brought the 15,000 spectators to their feet.
He skidded in from the baseline to retrieve a drop shot and then ran back to the baseline to whack a blazing passing shot winner off a Djokovic lob.
That provided the spark the British third seed needed to ignite his floundering game and he duly scorched Djokovic by breaking him with another passing shot that the Serb misfired vertically into the air.
A backhand service return long from Djokovic meant that at 7.49pm local time, the Serb, who beat nine-times champion Nadal two days ago, lost his first set at Roland Garros in 2015.
Both men will return at 1100 GMT on Saturday to complete an intriguing battle that will either keep alive Djokovic's dream of becoming the eighth man to secure a career grand slam or make Murray the first British man to reach the Paris final since Bunny Austin in 1937.
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