Hello, and welcome to Sports Mole's coverage of the French Open quarter-final match between Novak Djokovic and Tommy Haas.

This has the potential to be a really close match. The likelihood is that Djokovic will find a way to prevail past his veteran opponent, but Haas has been superb in this tournament so far, and who knows, maybe he can continue his fine form.

The players are already at either end of the Suzanne Lenglen court, and we are ready to go. Haas to serve first.

Djokovic looks strong on the opening three points, moving into a 15-30 advantage, but he misses an opportunity to earn two break points when a forehand catches the net. His German opponent then forces another error from the world number one and he is on the board with a solid service hold.

Djokovic already looks a different man compared to his previous match against Philipp Kohlschreiber. He lacked authority on Monday, but he has come out firing today, taking the game to love.

However, despite Djokovic looking focused, Haas is coming into this encounter on the back of thrashing Mikhail Youzhny in the fourth round, and it is continuing here as he flies through a love-service hold of his own.

Haas takes the first point of the game, but it doesn't take long for Djokovic to regain control, concluding the game with back-to-back aces. There have been very few rallies so far, with many of the points being dictated off the first serve.

This game starts off more competitively, with Haas smashing the ball past his opponent for a 15-0 lead, before hitting long after a gust of wind interrupted the point. Both players then trade errors as they struggle to judge the wind, and we have 30-30. Haas trades with Djokovic from the baseline, and he brings up game point when the Serb goes long, before sealing the game with a big first serve.

More dominance from Djokovic on his serve, following a drop-shot winner with another ace for 40-0. Haas attempts a drop shot of his own, but he hasn't got an answer to the world number one's serve at the moment.

BREAK! The 35-year-old concedes the first point by netting from the baseline, before Djokovic enjoys some good fortune to move 0-30 up. The Serb nets on the next, but a glaring miss from Haas gifts Djokovic two break points. He does well to hold off his opponent during a high-quality rally to save the first, before a smash brings up deuce. Haas is remaining on the offensive, but he goes for too much on a backhand and it is another opportunity for Djokovic, who makes no mistake with a crushing forehand down the line.

There is so much control in Djokovic's play at the moment that you can't see Haas getting a look in if he doesn't drop his standard. A whipped forehand down the line and an ace give him three game points, before Haas goes long off a return. Djokovic has won 16 out of 17 points on his serve.

SET! Haas is making a concerted effort to change things up, but he still falls 0-30 behind. A first serve reduces the deficit, but a fine return from Djokovic catches Haas in no-man's land, and it's two set points. Haas saves the first, but a superb driven forehand gives Djokovic the opener.

Djokovic is relentless behind his first serve, swiftly moving to game point with a delicate drop shot at the net. He then sends down yet another ace, and that is 20 out of 21 points in five service games.

The 35-year-old restores some confidence with a couple of easy points on his serve, before double-faulting. However, two more big serves get him on the board for the second set in next-to-no time.

Djokovic batters Haas with several forehands in a row before he eventually relents. The German is on the ground after slipping on the side of the court when returning serve, but he appears to be ok after chasing down a lob on the run from Djokovic to smash the winner. That was just his second point on the Serb's serve. However, Djokovic restores normal order with a miraculous sliding drop shot that Haas has no response to.

The first serve of Haas is vital to the direction in which this match will take, but even three decent serves can't prevent him from falling 15-30 behind. However, he keeps the pressure on, and Djokovic can't do anything with the next two, before a backhand down the line from the Serbian goes wide.

The German is beginning to get into more rallies on Djokovic's serve, but it is almost as though the world number one is toying with him as he picks him off at will at the net. Another ace helps Djokovic to the game, which is his fifth love-service hold.

Another forehand error doesn't help Haas, but his first serve is continuing to help him out of trouble and he quickly gets back to 30-15. However, again, the forehand lets him down at the end of a lengthy rally, before he nets a backhand after a sharp return from Djokovic. He saves the break point with a ace out wide, and another powerful serve brings him game point, which he takes by coming out on top with a lob after some impressive defensive work from the Serb.

Haas takes the first point, but he lets out his frustration when he makes a big forehand error. Djokovic soon regains control of the game, and his veteran opponent nets to hand him another easy hold of serve.

These two are really flying through the points. We have only just reached the hour-mark in this match, and it is easy to see why as Haas wins four points off his first serve and we are reaching a crucial part of this match.

Djokovic starts the game with an ace, before he moves to game point with a deft backhand drop shot that Haas can't chase down. A sixth love-service game is won when he fires a forehand back at Haas after he could only return the ball to the middle of the court.

That's classy from Haas, who sends a single-handed backhand down the line, but he goes on to make errors on both sides to hand his opponent 15-30. He does well to avoid conceding two sets points by forcing Djokovic into a forehand error, which he builds on with a stunning first serve. That's quite a response from Haas, who seals the game when Djokovic sends a return long.

This is one of the finest serving displays that I have ever seen. Two drop shots from Djokovic come either side of his ninth ace, before he forces another forehand error from Haas. Djokovic now has seven love-service holds, while only conceding three points on serve in 10 games.

Haas is serving to stay in this second set, and it is a shaky start from the 35-year-old, who sends a forehand long of the baseline. He replies well, however, forcing Djokovic to net, but the Serb responds with an impressive passing shot for 15-30. Two errors from Djokovic hand Haas game point, but he then nets to bring up deuce. This game could go either way, but it's Haas who strikes to bring up game point with a backhand winner. Djokovic then goes long with a backhand slice, and we have a tie-break.

Haas takes an early mini-break with a fine backhand, but he then spoils that hard work with a forehand error. Two big serves from both players make it 2-2, before a Djokovic forehand clips the top of the net and Haas regains the mini-break. The intensity of the rallies have increased, but it is Haas who is now coming out on top, and he has the 4-2 advantage at the change of ends.

However, Djokovic isn't the world number one for nothing, and he forces two forehand errors out of Haas for 4-4, before recording a 10th ace and we are back on serve. Haas is fortunate when a shot from Djokovic is millimetres over the baseline, and we are at 5-5. We are treated to a world class rally on the next point, which ends in Djokovic sending a cross-court winner past Haas and he has set point. The world number one finds the first serve, and Haas goes wide, and Djokovic moves one set away from the semi-finals.

Djokovic is in the ascendancy when he moves to 0-30 lead, but Haas, who is visibly frustrated, hits back with four aggressive points, completing the game with a cross-court backhand. He needed that.

Before the start of the game, Djokovic had lost just five points on his serve in two sets, and while that figure has now moved to six, he eases to another service success with three cleverly-worked backhands down the line.

BREAK! Could this be the moment? Djokovic takes the first point with another winner from a drop shot, before he beats the German at the net. Haas then makes an error from the baseline and it is three break points for the world number one. He wastes no time in forcing the 35-year-old back, and Haas goes long to edge nearer to defeat.

BREAK! Haas nicks the opening point, before a deep second serve allows Djokovic the space to hit a backhand winner. However, some heavy hitting then brings Haas his first break points of the match, and he is back in this match after Djokovic sends a forehand yards long of the baseline.

It's fair to say that the outcome of that last game was unexpected! Djokovic makes an error on the first point, but he establishes control with a super drop-volley at the net. A backhand winner restores parity for Haas, and after Djokovic goes wide, he whips another backhand winner for the game.

Djokovic needs to steady himself here because Haas is threatening to change the course of this set. He is successful in moving to 30-0, and he achieves game point when Haas sends a forehand return long. That's a terrific shot from Djokovic to conclude the game, driving the ball to the far corner of the court.

BREAK! The two players share the opening exchanges, before Haas rockets a winner down the line. Djokovic stuns him with a sharp return, forcing the German to net, but Haas regains the initiative when Djokovic drifts the ball long, but the Serb hits back with two massive forehands to bring up deuce. There is a huge cry of frustration from Djokovic after missing a relatively easy forehand, but he is made to feel easier after a double fault from his opponent. It's Haas who is agitated now after Djokovic brings up break point, and the 35-year-old relents, sending a backhand wide of the line.

Djokovic will be eager not to let his advantage slip this time, and a couple of well-worked points give him 30-15. He then connects with a first serve down the middle and he has two game points, before moving one away from the semi-finals with a smash.

That's some recovery skills from Djokovic, who somehow comes out on top at the net, but Haas responds with an unreturnable first serve. The Serbian player replies with two huge returns of serve to earn his first match point, but he can only net when the chance was there to hit the winner. Haas does fantastic to hang in there on the next two points to ensure that Djokovic must serve for the match.

BREAK! It's a shaky opening from Djokovic, who goes long, before a superb passing shot from Haas gives him 0-30. The world number one sends down another ace, before stepping in to drive a forehand winner for 30-30. It looks set up for Djokovic to earn match point, but two errors in a row hand Haas the break. Can he find something extra to fight back in this match?

BREAK! Djokovic goes long on the opening point, but a double fault makes it 15-15. The pair then make two more unforced errors, before Haas sends a forehand flying over the baseline to hand Djokovic break point. What a reply from Haas, who records an ace out wide for deuce, and he follows that up with a second, before Djokovic finds the line with a forehand. It's hit or miss from Haas at the moment, and he misses again to give the Serbian another chance, but the world number one doesn't take advantage. Haas is slowing down a tad, and he serves up another double fault. Djokovic has a third chance to break, and this time, he takes it when the German goes long from the baseline.

MATCH! Haas whips a forehand long on the first point, before sending a backhand in the same direction after attempting to take the ball on the rise. Djokovic brings up three match points when he outlasts Haas from the baseline, and he is through to the semi-finals with a backhand winner down the line.

Novak Djokovic is through to the last four after outlasting 35-year-old Tommy Haas. The world number one dropped his level near the end of the match, but it was an impressive display from the 26-year-old, who will now go on to face Rafael Nadal on Friday afternoon.

As for Haas, he can be pleased with his run in the tournament. He would have been disappointed to have lost the second set, but he was beginning to wilt near the end of the third, and it was only a matter of time before Djokovic moved through to the next round.

That is all for Sports Mole's tennis coverage this afternoon. We hope to see you again tomorrow for the two women's semi-finals. Goodbye for now.