Celtic travelled to Lisbon tonight knowing that a score draw with Benfica would see them all but qualify for the knockout stages of the Champions League.
The Portuguese outfit trailed Neil Lennon's men by three points with this being the penultimate game, and needed to win to have any real chance of qualification.
The Hoops managed to get to half time on level terms, but were undone by a fine effort from Ezequiel Garay 20 minutes from time.
Benfica are now second in the group by virtue of a better head-to-head record, but face a daunting trip to the Nou Camp in their final game, while Celtic host Spartak Moscow.
You can read how the action unfolded below.
Good evening! We're at the business end of the Champions League group stages and the second qualifying spot in Group G is well and truly up for grabs.
Tonight Celtic travel to Lisbon to face Benfica, who they lead by three points with two games remaining.
A draw tonight would almost certainly see Celtic progress to the knockout stages. It's a game that Benfica simply must win.
Celtic return to the city where they won the trophy for the only time in their history back in 1967 with the famous Lisbon Lions.
Celtic return to the city where they won the trophy for the only time in their history back in 1967 with the famous Lisbon Lions.
Barcelona have already qualified from Group G. Celtic are on seven points, while Benfica are on four. Celtic host Spartak Moscow on the final day, while the Portuguese team travel to the Nou Camp. It's delicately poised...
We have some team news for you...
Forster; Lustig, Ambrose, Wilson, Matthews; Brown, Wanyama, Ledley, Mulgrew; Hooper, Samaras
The last time Celtic won in Portugal was in 2003, when they triumphed 1-0 over Boavista. Benfica have only faced one other Scottish side. They beat Hearts 3-0 in in 1960/61.
Apologies for the multiple posts, a quick manual refresh should sort the problem.
Lennon: "[We have set up] not to be defensive. We want to play the way we normally play. What we really want is to get a point tonight, or three."
Celtic's team is more attacking than the one that faced Barcelona. Lennon has gone with two up front in Hooper and Samaras and is clearly trying to get a result tonight that would ease any tension that would exist against Spartak Moscow in two weeks' time. It's a gamble, but a calculated one.
There's a lot of emphasis on Fraser Forster tonight. He almost kept Barcelona at bay in the Nou Camp, but succeeded in his task at Celtic park two weeks ago. The Spanish have dubbed him 'La Gran Muralla' - The Great Wall.
Sorry, that should be 'La Gran Muralla'. Drop the D. That's what you get for trying to be clever.
The players are making their way onto the pitch. We're just minutes from kickoff at the Estadio da Luz.
Celtic are in all black with green trim, Benfica in their customary red and white. Hungarian referee Viktor Kassai takes charge of tonight's contest.
Benfica get the game underway...
Wilson makes the first tackle on Lima. He slides in well to put it out for a throw.
SHOT! Samaras is dispossessed in midfield and Cardozo takes a shot on from long range but it goes over Forster's bar.
It's been an efficient start by Celtic. They have not lost their shape or come under any pressure so far. Just what they wanted.
GOAL! Benfica 1-0 Celtic (John)
And just when I was praising their defensive work, Celtic make a hash of a clearance and panic strikes their ranks. The loose ball breaks to Ola John inside the area and he smashes low past Forster. I spoke too soon.
The crowd are at ease now as Benfica sweep the ball around. Celtic are finding it hard to have a touch of the ball.
Celtic go forward for the first time but Mulgrew is closed down before he can get a cross into the box.
Hooper thinks that he's through on goal but the linesman is flagging. Replays showed that he was onside. It was a wonderful through ball by Ledley. So unlucky.
Wilson waits for the ball to come to him in the centre of defence while Cardozo is fast approaching behind him. He was completely unaware of his presence, and there didn't seem to be a shout from a teammate. Celtic need to switch on here.
It's raining heavily in Lisbon and it's suiting Benfica's slicker passing style. Celtic can;t get enough players forward and the hosts are enjoying all the possession. The play is just getting a bit stop-start at the moment due to a few petty fouls.
Although Perez has just smashed into Wanyama and is bleeding from his mouth. He's off the pitch receiving treatment.
Celtic have possession of the ball but the crowd are booing hysterically as the referee is preventing Perez from returning to the field of play.
CHANCE! Wilson plays a slack pass out of defence and Salvio picks it up. He slips in Cardozo, but he slashes his left-footed shot wide of Forster's goal. Let off.
Celtic have a corner...
GOAL! Benfica 1-1 Celtic (Samaras)
Mulgrew delivers a peach of a cross and the Greek finds himself unmarked at the back post to head Celtic level!
SHOT! Samaras finds some space for himself and has a go from 25 yards out but it trickles harmlessly wide.
Celtic are having more of the ball in advanced positions now. It's been a good five-minute spell for them, but how long can they keep it up?
Samaras brings down Matic and Benfica have the chance to launch the ball into the box.
Ola John delivers but it's cleared and Samaras tries to break down field, but the referee blows up for a foul and gives the striker a yellow card.
Ola John delivers but it's cleared and Samaras tries to break down field, but the referee blows up for a foul and gives the striker a yellow card.
Ola John delivers but it's cleared and Samaras tries to break down field, but the referee blows up for a foul and gives the striker a yellow card.
Ola John delivers but it's cleared and Samaras tries to break down field, but the referee blows up for a foul and gives the striker a yellow card.
SAVE! The ball falls to John on the left side of the area and he has a go at goal but Forster saves with his legs.
SAVE! The ball falls to John on the left side of the area and he has a go at goal but Forster saves with his legs.
Benfica 1-1 Celtic
Benfica piled on the pressure as Celtic desperately held out for the whistle. A big 45 minutes now approaches for Neil Lennon's men. If it stays like this, then they're virtually unassailable. If they can win, they qualify. What they won't want is to start the second half as they did the first.
You can read Sports Mole's Half-Time Report by clicking here.
Elsewhere in the Champions League, Chelsea are trailing Juventus 1-0 in Turin. It's goalless between Galatasaray and Manchester United in Turkey. Valencia and Bayern Munich is also 0-0 at half time.
Barcelona defeated Spartak Moscow in the other game in this group earlier on.
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The players are back on the field and we're ready for the second half.
Celtic resume play...
Beram Kayal comes on to replace Charlie Mulgrew, who is 'feeling unwell'.
Joe Ledley goes into the book for a dangerous tackle on Almeida.
Celtic are working really hard. They need to stay switched on though, as one little slip could be disastrous.
CHANCE! Lima outfoxes Ambrose and gets in down the left, he cuts inside and shoots past Forster but Matthews clears off the line!
I beg your pardon, it was Matthews who made the clearance. Fantastic defensive instinct. Not so much from Ambrose.
Salvio takes a driven corner and it breaks to Perez on the edge of the box, but he fires well over.
Celtic are scrambling a bit in defence and Benfica have another corner.
Luisao scoops over the bar from eight yards out!
Big chance for Benfica! They should be leading!
Benfica are pressing forward now and it's one-way traffic. Matic tries a long-range volley but it sails well over.
Celtic have gone very narrow now and Benfica are profiting out wide. Kris Commons is readying to come on and it looks like Scott Brown is the man coming off.
Scott Brown makes way for Kris Commons.
The captain comes off struggling with a hip injury and hands the armband to Samaras.
Corner to Celtic...
Commons swings it in and Artur is farm from convincing in parrying out. It's left to a defender to hack clear.
Matic brings down Samaras and Commons has another chance for a telling delivery...
And Samaras nearly gets his head on it! It didn't look like he knew too much about it with players jumping in front of him.
SHOT! Lima tests Forster but the Englishman is up to the task as he gets down low to save.
CHANCE! Salvio comes flying in but can't get anything on Lima's cross!
GOAL! Benfica 2-1 Celtic (Garay)
The Celtic defence stood static as Luisao beats Ambrose in the air to knock the ball down for Garay to volley home first time! Brilliant finish!
SHOT! Wanyama tries to bend one with his right foot but Artur palms it away.
OFF THE BAR! Salvio strikes one that has Forster beaten but not the cross bar!
Lima makes way for Nicolas Gaitan.
Melgarejo is booked for kicking the ball away.
Maxi Pereira comes on for Nemanja Matic.
Tony Watt comes on to replace Joe Ledley.
SAVE! Cardozo strikes a fine free kick towards the top corner but Forster gets his fingertips to it!
Kayal nearly slips in Commons but the ball is intercepted. It breaks to Lustig but his cross is poor.
Victor Wanyama receives a booking that will rule him out of the Spartak Moscow game!
SHOT! Tony Watt gets onto Samaras's pass and has a go from around 25 yards, but he doesn't really get hold of it.
SAVE! Cardozo flicks it past Ambrose and has a golden opportunity but Forster denies him! Another one!
Jardel comes on for Eduardo Salvio.
Celtic launch the ball into the area and Kayal is in space for the volley but blazes it over the bar!
We're going to have three minutes of injury time at the Estadio da Luz.
Celtic pile forward! The ball is pumped into the box and it falls to Watt at the back post, and he drives it across the face of the goal. Hooper was agonisingly close to getting a touch!
Benfica 2-1 Celtic
So it's going down to the wire. It's by no means unthinkable that Celtic will go through. They play Spartak Moscow at home, while Benfica travel to Barcelona. Neil Lennon will be hoping the Catalan giants can do the business and sign off Group G with a win. If they do, Celtic will need just a point against the Russian team. It's set up to be a thrilling finale, so please join us for it in two weeks' time!
