Chelsea travelled to Juventus this evening knowing that a victory in Turin would secure their passage through to the last 16 of the Champions League.
As it was, the defending champions were well beaten by their hosts by three unanswered goals.
The result has left Chelsea's hopes of advancing hanging by a thread.
Read how the match unfolded with our minute-by-minute updates below.
Evening all. What a match we have in store this evening. Looking at the fixtures, it has to be the biggest match of the night doesn't it?
Before we get into why that is the case, the team news is now beginning to break. Here is what we know...
JUVENTUS X1: Buffon; Barzagli, Bonucci, Chiellini, Lichtsteiner; Vidal, Pirlo, Marchisio, Asamoah; Quagliarella, Vucinic
The big news from a Juventus point of view is that Mirko Vucinic has been passed fit and starts up front. He was dangerous during the first meeting between the two clubs. Meanwhile, former Manchester United midfielder Paul Pogba will begin the match on the bench as Andrea Pirlo returns to the starting lineup.
We are still waiting for Chelsea to show their hand. If reports are to be believed, Fernando Torres may be dropped for this one. Surprisingly Eden Hazard has been tipped to start up front.
BREAKING: Fernando Torres does in fact start on the bench for Chelsea. The full lineup will be coming very shortly...
CHELSEA X1: Cech; Azpilicueta, Cahill, Ivanovic, Cole; Luiz; Ramires, Mikel; Mata, Oscar; Hazard
The decision to drop Torres has come across as a big one. But when you break it down and look at his goal return and performances, it's not massively surprising. He has been poor since joining from Liverpool in 2011. One thing that will be interesting is how the Blues function without a recognised frontman. It looks as though they will mimic the Spain team from Euro 2012.
The other talking point in that lineup is the inclusion of five defenders. Looking at the quintet, it appears that either David Luiz will play as a holding midfielder, or Cesar Azpilicueta will start on the right wing. The latter seems more likely.
Right, let's move on from that Chelsea team and look what the results could mean this evening...
A victory for Chelsea would quite simply see them reach the final 16. A draw would leave them needing to beat Danish side Nordsjaelland at Stamford Bridge on matchday six to advance. A defeat means that they would have to overcome Nordsjaelland and hope that Shakhtar Donetsk do them a favour against Juve. Best win tonight then!
Of course these two sides met at the Bridge earlier in the group stages in what was an extremely entertaining night. It was a match where Chelsea midfielder Oscar announced his arrival with two impressive strikes. However, Juve battled back and claimed a 2-2 draw. If they lose tonight, Chelsea may look back letting that two-goal lead slip as a crucial moment in qualification.
For those of you who have forgotten Oscar's performance that night (not sure how you could) here's the pick of the two goals:
One statistic that doesn't bode too well for Chelsea is the fact that they have only won twice from their last nine Champions League away matches. Still, a draw would probably be a decent result for Di Matteo's team.
Enough of Chelsea for a minute or two though, let's pay some attention to their hosts...
They were impressive at the Bridge earlier in the competition. As mentioned earlier, Vucinic looked sharp. However, the player that really caught the eye was Arturo Vidal. He looks to be an old fashioned midfielder who is capable of attacking and defending. His form has seen him linked with Manchester United recently and he looks as though he would be a welcome addition to their midfield.
These two sides actually met in this competition back in 2009 for a place in the quarter-finals. Following a 1-0 victory in London, Chelsea progressed courtesy of a 2-2 draw in Turin. Didier Drogba got two of Chelsea's three goals over the two legs - how they could do with him tonight!
Here's some of what former Chelsea full-back Graeme Le Saux has told BBC Sport about the fixture:
"Chelsea will certainly not be all guns blazing going forward. They have been so flamboyant this season with Hazard and Oscar and Mata being all really exciting to watch, but they can't be as free-spirited tonight.
"They have got to show a lot more discipline, the same discipline they showed last season in the Champions League when they went on to win it. They will look to catch Juventus on the break."
Meanwhile, Di Matteo has just been talking to ITV Sport: "We want to not give them a point of reference. You will have to wait and see to see if it is a change of system. We wanted to change something for this game because we need a positive result."
Right, the players are in the tunnel waiting to come out. Have to say that there is a cracking atmosphere inside the Juventus Stadium tonight.
We've just had the Champions League anthem. Gets you every time doesn't it?! Chelsea will get this crucial encounter off and running.
At the moment it looks as though Oscar and Hazard are going to share the striker's role. Chelsea have seen a lot of the ball during the opening exchanges.
OFF THE POST! What a stop from Petr Cech. It looked as though Lichtsteiner was going to put Juve in front at the back post but the Chelsea goalkeeper threw himself at the ball and the danger was cleared via the post. Big escape for the Blues.
Chelsea really need to settle here. They're giving the ball away too easily at the moment. Ramires in the midfield has been the main culprit.
SAVE! Another cracking piece of goalkeeping, this time from Gianluigi Buffon. Oscar made a great run into the Juve half and threaded a pass through for Hazard. The Belgian took one touch, before seeing his shot hit the side netting courtesy of a deflection off of Buffon.
Other than that Hazard chance, Juventus have dominated this match. They've had a number of corners that have come to nothing and continue to press Chelsea. It seems that it is only a matter of time until they score if they keeping going like this.
SAVE! A clever corner routine from Juve ends with Cech tipping Claudio Marchisio's powerful drive around the post.
Fabio Quagliarella, who scored in the first match, has just had two sights of goal in quick succession but both rolled tamely towards Cech, who didn't have to move.
Chelsea are offering very little as an attacking threat. That's got a lot to do with the fact that they have nobody to aim for. The likes of Oscar, Mata and Hazard are getting their heads up and are having to turn back.
SAVE! A routine stop for Cech as Pirlo drives a low freekick straight into his hands. Juve continue to knock at the Chelsea door.
It's all gone a little scrappy from Juve. Passes that have been sticking are now going astray. Some of the credit has to go to Chelsea, who are now making their opponents work hard in possession.
Chelsea are now having some time on the ball. It's breaking down in the final third at the moment, but at least they are competing.
CHANCE! Good opportunity for the Blues as Ramires bursts through the midfield and threads a pass through to Oscar. He has to get the ball on his right foot though and the danger is eventually cleared.
GOAL! Juventus 1-0 Chelsea (Quagliarella)
Cech has been almost faultless so far but you have to look at the Chelsea goalkeeper here. Granted Quagliarella's shot takes a deflection, but Cech was slow to adjust himself and the ball squirms into the Chelsea net. The Blues are up against it now.
DOUBLE CHANCE! At one end Ashley Cole clears off the line to prevent Chelsea going two behind, before the Blues go on the attack which ends with Mata firing straight at Buffon from close range. That was a wasted chance for Di Matteo's side.
HALF-TIME: Juventus 1-0 Chelsea
Well, it's not been the greatest half that Chelsea have ever played! They are playing without a recognised striker and it is showing! Cech may have been slightly to blame for the Juve goal, but without him they would be even further than one goal behind.
Just to keep you up to date, Shakhtar are drawing 2-2 in Nordsjaelland. If the Danes can hold on, that would be a big, big boost for both of these teams.
Juventus have got the match back underway in Turin. Big 45 minutes for Chelsea...
SAVE! First sight of goal of the half for Juve ends with Vidal drilling a shot straight at Cech from 20 yards out. It's been a bright start from the hosts.
PENALTY APPEAL! A massive shout from Juventus and Vucinic is waved away by the referee. Have to say replays show that the striker was pulled back by Chelsea defender Gary Cahill. A big call - and possibly the wrong one.
Bad news for Chelsea. As it stands qualification is no longer in their hands as Shakhtar take a 3-2 lead in Denmark.
SAVE! An ambitious effort from Pirlo is turned wide by Cech. It was a fantastic hit by the midfield maestro.
SUBSTITUTION: First switch of the night for Chelsea sees Victor Moses take the place of Azpilicueta. That's a sign of intent from Di Matteo.
GOAL! Juventus 2-0 Chelsea (Vidal)
It's a long, long way back for Chelsea now. Asamoah was the creator, cutting the ball back for Vidal on the edge of the area. The Chile international took an instant shot, which beat check via a deflection off of Ramires. That should be the game for Juve.
More bad news for Chelsea as Shakhtar have added a fourth in Denmark. It looks as though the Ukrainians will stay top, while Juve move up to second.
SUBSTITUTION: Here comes Torres for Chelsea. He has replaced the holding midfielder Mikel. If there was ever a time for Torres to endear himself to the Chelsea faithful, it's now.
CHANCE! Vucinic really should have put the game to bed there. He found himself with time and space inside the area but lifted his effort well over the bar.
Chelsea are offering very little as an attacking force now. They look like they know that the game is up. Torres has barely touched the ball since he came on, nor has Moses.
SUBSTITUTION: Vucinic takes his leave for Juventus as the pint-sized Sebastian Giovinco takes his place.
It's now 5-2 to Shakhtar - they're not messing about are they?! This group will go down to the final day.
Chelsea are now seeing a lot of the ball as Juventus drop a little deeper to protect what they've got. They look extremely comfortable defending their own goal though. I can't remember the last time Chelsea had a shot!
SUBSTITUTION: Here's one for Man United fans. Your former midfielder Paul Pogba has replaced goalscorer Quagliarella.
GOAL! Juventus 3-0 Chelsea (Giovinco)
That rounds off a rather poor evening for the Blues. Cech races out of his area but he's well beaten by a speedy Giovinco, who slots the ball underneath the advancing goalkeeper and into the net. He was booked for his celebration as well.
There will be three minutes of stoppage time by the way...
FULL TIME: Juventus 3-0 Chelsea
A night to forget for Chelsea and what's worse is that qualification for the next round is no longer in their hands. They will need Shakhtar to defeat Juventus next time out or they will become the first defending champions to lose out in the group stages.
That's all we have for you from Turin. Thanks for joining us this evening and be sure to check out our analysis, which will be coming your way shortly.
