Venue: Roland Garros, Paris Date: 23 May-6 June
Coverage: Live video streamed from 1000 BST on BBC Sport website (UK only) and BBC red button; commentary on BBC 5 live sports extra; also live on Eurosport; text commentary on BBC Sport website
Details of BBC coverage
Djokovic followed number one seed Roger Federer out of the French Open
By Piers Newbery
BBC Sport at Roland Garros
Third seed Novak Djokovic let a two-set lead slip as he went out of the French Open to Austria's Jurgen Melzer in a dramatic quarter-final.
Melzer, the 22nd seed, came through 3-6 2-6 6-2 7-6 (7-3) 6-4 after four hours and 15 minutes on a pulsating Court Suzanne Lenglen, and he will face Rafael Nadal in the last four.
"I told myself, 'It's my first quarter-finals in my life in a Grand Slam, just don't go away. Just don't make it easy for him. Fight as much as you can,'" said Melzer.
"And I wasn't playing so bad, I just missed a lot of easy shots when I had the chance and the opportunity to finish the point.
"After that I got back in, and at 2-2 in the third it was an open match. I think I got a little under his skin after the third set."
Djokovic, who has been struggling with an allergy in recent weeks, ran out of steam alarmingly having sailed through the opening two sets.
When he broke serve early in the third a comfortable win appeared minutes away but, over two hours later, the 23-year-old Serb found himself facing two break points at the start of a deciding set.
Melzer, 29, had begun to take his serve apart but struggled to make his dominance count, converting only three of an amazing 19 break points in the first four sets.
Another four would go begging in the decider and it appeared that Djokovic might escape with his seventh win in eight matches over five sets.
Melzer's 24th break point of the day proved the clincher as Djokovic played a desperately poor volley when the ball appeared to be going long.
But the Austrian, playing in his first Grand Slam quarter-final, still had to serve out the match and there was more drama to come.
A stinging Djokovic forehand looked to have taken him to 0-30 only for the umpire to check the mark and overrule, prompting a furious outburst from the Serb.
Moments later, Melzer played a woeful volley into the net on his first match point with the empty court gaping as Djokovic, and the crowd, sensed yet another twist in this extraordinary match.
I'm very disappointed, obviously, to lose the match that I was in control of totally a set and a break
It was not to be, however, and Melzer became the first Austrian since Thomas Muster in 1995 to reach the French Open semi-finals when Djokovic fired a forehand over the baseline on the second match point.
"I want to congratulate him first," said Djokovic. "I think he played really well in the last three sets but I made a big mistake.
"I made him come back into the match with my unforced errors and then he caught the momentum and he was playing really well, especially on his service games.
"I'm very disappointed, obviously, to lose the match that I was in control of totally a set and a break. This is tennis, you know. This is Grand Slams. You always have to play up to the end because these things happen, especially at this stage of tournament."
And despite being unhappy with the line call in the final game, the Serb admitted the umpire was not the reason for his defeat.
"I don't know what was going on with him but the ball was looking good from everywhere," said Djokovic. "Even on the TV you could see it was good but I can't blame him for losing this match, of course. That's one call."