Read how it all unfolded on Centre Court in our game-by-game updates below.
6.25pmEvening folks. It's been a wonderful day of tennis so far at the All England Club and I think it's about to get even better now.
6.28pmWe've already seen one top seed eliminated today, could we see another sensationally exit on Manic Monday?
6.29pmI think that Haas certainly has a good shot of defeating Djokovic today as he's playing some fantastic tennis at this year's Championships.
6.30pmH2H: Djokovic leads the pair's head-to-head overall but Haas has won both of their previous meetings on grass. They were, however, four years ago in 2009.
6.31pmJust before we start on Centre, let me tell you what's happening on No. 1 Court. Bernard Tomic and Tomas Berdych are now into a tie-break and you can follow it with Liam Power here.
6.32pmIt'll be Haas to serve first. Play...
6.33pmExtremely nervy start from the German, missing an easy volley to start before Djokovic passed him at the net. The Serb now has three break points as Haas double faults!
Djokovic *1-0 HaasBREAK! Haas saves the first two but can't bring it back to deuce as Djokovic finds the corner and the German can't curl it into play.
6.36pmGoodness me, I would never have believed you if you'd told me that both men would double fault in their opening service games! Djokovic has now as well and Haas is after that break back at 15-30.
6.37pmAnd now 15-40 and two break-back points for Haas...
6.37pmAmazingly Djokovic hasn't been broken at this year's Championships and he saves the first with an ACE.
6.38pmPoor from Haas as he carelessly hits long mid-rally to surrender the break chance. Back to deuce.
6.39pmBetter from the German as he dominates the baseline and has a third chance to break back...
6.39pmDjokovic finds a first serve and Haas can't nudge it back in play.
Djokovic 2-0* HaasDjokovic comes through after saving three break points. He's still to be broken at this year's tournament. Haas should be furious with himself.
Djokovic *3-0 HaasDOUBLE BREAK! Dear me. Haas has been serving so well this year but he's just given away his serve for a second time, this time to love. Is that the first set already over?
6.44pmThe royal box is quite empty at the moment as the lucky ones invited there grab a drink. One man who is back in his seat is Ryder Cup hero Ian Poulter and he's shown scoffing down some sweets out of a champagne coolbox. Jealous doesn't quite cut it.
Djokovic 4-0* HaasDjokovic is hardly dominant on his serve at the moment but he closes out another game with an ACE at 40-30. Haas just needs to get on the board here to settle him down.
6.48pmHaas continues to struggle on serve as Djokovic moves to 0-30 thanks to a pair of missed forehands from the German.
Djokovic *4-1 HaasThe 35-year-old wins the next four on the trot though, including his first ace, and he's on the board at last. Expect him to play much better now.
6.50pmI've been really surprised by the relatively poor standard of both men so far. Djokovic does have a double break but if Haas had turned up in the first five games then it could be the other way round.
6.53pmDjokovic moves to 40-0 but Haas shows that he's still an agile fellow by tracking down a drop shot and clipping it deftly crosscourt for a winner.
Djokovic 5-1* HaasHaas can't make the return on the next and Djokovic is now one game away from the opening set.
6.56pmDjokovic finds a brilliant return winner to prevent Haas holding at 40-30 and now it's SET POINT to the Serb as Haas mishits.
Djokovic 6-1 *0-0 HaasSET! Haas with an ugly miss off an easy smash that hands Djokovic the set.
6.59pmI really am astonished at how badly Haas played there. Djokovic was far from his best too but he didn't need to play any better than he did.
Djokovic 6-1 1-0* HaasDjokovic is off and running in the second as he holds to 15. His opponent Haas to hold serve now to boost his confidence.
7.06pmHaas has chances to close out the game but Djokovic saves them and we're back to deuce. Come on Tommy, hold serve and make this a contest!
Djokovic 6-1 *1-1 HaasHe does! Hopefully the German is feeling a little more at ease and he'll now try and break the Djokovic serve for the first time this tournament.
7.09pmA glimpse of a break for Haas at 30-30. Can the veteran earn a break point?
7.09pmNope. Djokovic finds a first serve up the middle and Haas can only get his outer frame to the ball.
Djokovic 6-1 2-1* HaasIn the next rally Haas goes on the offensive but his forehand approach is long and that's his ninth unforced error of the match.
7.13pmHaas moves to 40-0 but we're now back at 40-30 after a phenomenal return from Djokovic right on the baseline.
7.14pmAnother unforced error from Haas sees us back to deuce. He completely bossed that rally but gave it up with a long backhand.
7.16pmGreat stuff from Djokovic as he plays some classic grass-court tennis to prevent Haas winning the game, approaching with a deep slice before putting away the volley on the second occasioin.
7.17pmHaas hit a careless forehand to offer Djokovic the chance to break but he's just saved it with an ace.
Djokovic 6-1 *2-2 HaasGood hold for the German as he smashes a Djokovic lob past the Serb. At least he's competing much better in this set.
7.21pmDjokovic hits long with a backhand and again it's 30-30 on the number one seed's serve. Can Haas earn a break point?
7.21pmYes, he can! Djokovic with another unforced error and it's BREAK POINT Haas...
7.22pmThat's so good from Djoko. He finds an ACE to bring it back to deuce.
7.22pmHaas punches his grip and gestures angrily to his box after hitting the net with a forehand. Djokovic now with a chance to hold.
7.23pmHaas is sticking around though, matching Djokovic at the baseline and we're back to deuce.
7.24pmAnother break point now for Haas as Djokovic's up-the-line backhand drifts wide...
Djokovic 6-1 2-3* HaasBREAK! Wow. Haas balloons up the Djokovic serve and it should be an easy forehand putaway for the world number one but he drags it down into the net. Who saw this coming after the first set?!
7.26pmWill Haas now show confidence and move clearly ahead in this set? He wins the first point as Djokovic misses again.
7.28pmAt 30-0 Haas goes for the line with a second serve but it's called wide. He challenges, but to no avail.
Djokovic 6-1 *2-4 HaasDjokovic's attempted drop shot at 40-15 doesn't even reach the net and Haas now has clear daylight in this set.
7.30pmAs well as this match turning into a bit of a humdinger, it's also very interesting over on No. 1 Court. Young Aussie Bernard Tomic has just taken the second set on a tie-break against seventh seed Tomas Berdych.
Djokovic 6-1 3-4* HaasDjokovic must be fuming at dropping his serve for the first time at the Championships and he's just menacingly held to love.
7.33pmNot a good start to the eighth game of this set as Haas's backhand doesn't trouble the court at all.
7.33pmAnd now the German's hands are on his hips after another miss, this time into the net.
7.34pmNot good at all! Haas is given a simple forehand putaway but pushes the forehand long and Djokovic now has THREE BREAK-BACK POINTS...
7.34pmThe first two are saved as Djokovic fails to get back a pair of serves.
7.36pmIt's an epic, epic rally at 30-40. On the 37th stroke Djokovic goes long with a backhand and we're back to deuce. What a point!
7.37pmDjokovic doesn't let that get him down though and he has another break point...
Djokovic 6-1 *4-4 HaasBREAK! An exuberant fist pump from Djokovic as another lengthy rally ends with his maybe-mishit backhand dipping onto the line. Haas challenges but it did hit the paint and we're back on level terms in the second.
Djokovic 6-1 5-4* HaasThe ascendency is with Djokovic now as he holds to 15. Haas now serving to stay in the set, and maybe the match.
7.43pmSurely there's no way the 35-year-old German could outlast marathon man Djokovic in five sets? He has to win this one.
7.44pmIt's classic Djoko defence as the Serb manages to get the ball back and with Haas in no man's land he can't make a volley so has to try an awkward half-volley that finds the net. 15-30 and dangerous times for Haas.
7.45pm30-40 and SET POINT Djokovic...
Djokovic 6-1 6-4 *0-0 HaasSET! Haas can't handle Djokovic on the baseline so decides to approach the net. His top-spin forehand isn't bad, but Djokovic is there and delivers a crosscourt pass that wraps up the second set in 49 minutes.
Djokovic 6-1 6-4 1-0* HaasWhat must Haas be thinking at the moment? He was 4-2 up in that last set but lost four on the trot to lose the set. Djokovic holds to 15 to start the third.
Djokovic 6-1 6-4 *1-1 HaasHaas won't give up, not yet anyway. He holds serve to get on the board straight away in the third set.
Djokovic 6-1 6-4 2-1* HaasHe's not troubling the number one seed's serve though as Djokovic holds to love.
7.58pmFantastic point to start the fourth game of the third. Both men leather the ball off both wings before Haas finally gets the better of the amazing mover Djokovic.
8pmHaas's slice doesn't get over the net and we're at 30-30 on the German's serve.
Djokovic 6-1 6-4 *2-2 HaasThe German wins the next two to hold serve. Djokovic falls on his bottom on the last point but he's OK.
Djokovic 6-1 6-4 3-2* HaasA 13th ace of the match brings up 40-0 for Djokovic but Haas prolongs the inevitable for a while with a fantastic shot. Djokovic says 'anything you can do, I can do better' with a delicate drop shot to hold.
8.07pmDjokovic with some extremely dogged defence but he can't stop Haas bringing it back to 15-15.
8.10pmBreak point Djokovic...
Djokovic 6-1 6-4 *4-2 HaasBREAK! Haas found a beautiful backhand midway through the rally but Djokovic yet again got the ball back before Haas blundered.
Djokovic 6-1 6-4 5-2* HaasDjokovic moves 40-0 ahead but Haas pulls it back to 40-30. The German can't stop Nole winning the game though and the number one seed is now a game away from the last eight.
Djokovic 6-1 6-4 *5-3 HaasHaas forces Djokovic to serve it out but surely he will do just that to book his place in the quarters.
8.18pmA tired slice from Haas and it's 30-0 Djokovic. I'm really surprised at how easy it's been for the world number one today. My prediction of a tough evening was way off the mark.
8.20pmAnother monster rally on Centre but this time it's Haas who wins it and we're back at 30-30.
8.21pmBrilliant again from Haas and he has BREAK-BACK POINT...
8.22pmSaved by the Serb thanks to a bullish forehand. He celebrates with a fist pump to the sky and we're at deuce.
8.23pmAnother break point for Haas as Djokovic's second serve is called in but Haas challenges. Replays show that it was a millimetre out. Djokovic grins as he thinks that the screen is saying his shot is in.
Djokovic 6-1 6-4 5-4* HaasBREAK BACK! Djokovic goes long with a forehand and somehow Haas has broken back in the third. Can he now hold serve himself with Djokovic still a game away from the match?
8.27pmThe crowd want this to go on and cheer loudly as Djokovic goes out on the first point.
8.28pmDjokovic with a stylish return winner at 30-0. Absolutely nothing Haas could do about that.
8.29pmMATCH POINT DJOKOVIC...
8.29pmSaved by Haas!
Djokovic 6-1 6-4 *5-5 HaasWhat a huge hold that is from Haas. Djokovic earned match point with some incredible defence but it was well saved by Haas before he closes it out to level the set.
8.32pmAt 30-0 Djokovic is given a high ball on the baseline, he blasts a forehand to the Haas backhand but it's the German who wins the point thanks to a phenomenal up-the-line winner.
Djokovic 6-1 6-4 6-5* Haas"Game Djokovic," as Haas lashes a backhand past the baseline. Are we headed to a third-set tie-break?
8.35pmAn encouraging start to the final game of the set for Haas as he gets the better of Djokovic at the net.
Djokovic 6-1 6-4 6-6(*0-0) HaasWe're heading to a tie-break on Centre!
THIRD-SET TIE-BREAKDjokovic 1-0* Haas. "Tommy, Tommy!" chant the crowd but Djokovic wins the first point.
THIRD-SET TIE-BREAKDjokovic 1-1* Haas
THIRD-SET TIE-BREAKDjokovic *2-1 Haas. Djokovic with the first mini-break as Haas nets a pass.
THIRD-SET TIE-BREAKDjokovic *3-1 Haas
THIRD-SET TIE-BREAKDjokovic 4-1* Haas
THIRD-SET TIE-BREAKDjokovic 5-1* Haas. Another mini-break for the Serb and the players change ends with Djokovic well in control here.
8.42pmHaas is disgusted with himself for missing an easy forehand on the last point.
THIRD-SET TIE-BREAKDjokovic *5-2 Haas
THIRD-SET TIE-BREAKDjokovic *6-2 Haas. FOUR MATCH POINTS for Djoko...
THIRD-SET TIE-BREAKDjokovic 6-3* Haas
THIRD-SET TIE-BREAKDjokovic 6-4* Haas. Two of them saved by the German.
Djokovic 6-1 6-4 7-6 HaasGAME, SET AND MATCH DJOKOVIC!
8.45pmThe number one seed launches an in-to-out forehand and turns his grunt into a victory roar as the ball lands in the corner.
8.46pmHaas will be gutted with the display he put in there. Djokovic was hot favourite but didn't have to play his best to beat the German today. The 35-year-old might not be seen at SW19 again and he waves to the crod before signing some autographs at the corner of the court. Nicely done, Tommy.
8.49pmNext up for Novak is seventh seed Tomas Berdych, who has just beaten Bernard Tomic in four over on No. 1.
8.52pmAnd so ends a wonderful day of tennis at Wimbledon. Relive it all on our SW19 hub of reaction, reports and commentaries here.
8.54pmSports Mole will be back tomorrow for the ladies' quarter-final day at the All England Club tomorrow. We'll see you then.