The result also saw the Portuguese side exit the competition at the group stage for the third consecutive season.
The only goal of the game came on 79 minutes when Zenit captain Danny found the net with a first-time finish from inside the penalty area.
Benfica's night went from bad to worse in stoppage time as their skipper Luisao was dismissed after picking up a second yellow card.
Read Sports Mole's minute-by-minute report below to find out how all of the action unfolded in Russia.
4.01pmGood afternoon and welcome to Sports Mole's live text coverage of today's early kickoff in the Champions League as Zenit St Petersburg host Group C rivals Benfica. These two teams currently occupy the bottom two places in the standings and a defeat for either would seriously damage their chances of reaching the last 16.
4.04pmIt was Zenit who triumphed in the reverse fixture between these two sides, claiming a 2-0 win in Portugal two months ago. However, since then the Russian have struggled thanks to one point from a possible nine. More dropped points today and they will be facing an uphill task in making it through to the knockout phase.
4.07pmIn contrast, Benfica started their Group C campaign with two defeats, but they have fought back in recent weeks to give themselves a chance of going through. Their upturn began with a goalless draw away to Monaco before a 1-0 win over the Ligue 1 side in Portugal made sure that they got some much-needed points on the board.
4.11pmZENIT SUBS: Malafeev, Luis Neto, Smolnikov, Shatov, Fayzulin, Tymoshchuk, Arshavin
4.14pmZenit coach Andre Villas-Boas has gone for pretty much the strongest team that he could have named this evening, with Javi Garcia, Axel Witsel and Hulk all included among the starting XI. Incidentally, Javi Garcia is one booking away from a suspension.
4.23pmBenfica's flamboyant coach Jorge Jesus has opted for the front three of Gaitan, Salvio and Lima tonight, while Lisandro misses out as he completes a two-game suspension. Salvio, Perez and Andreas Samaris are all one booking away from a ban themselves.
4.26pmRight, back to business. There are plenty of links between these two teams, with Zenit trio Witsel, Garay and Javi Garcia all having played for Benfica. Meanwhile, Zenit coach Andre Villas-Boas won four and drew three games against the Portuguese outfit when he was managing in his native country with Porto and Academica respectively.
4.29pmVillas-Boas: "Benfica have played good football in their last few games. The coach will have prepared them well for this, I know Jorge Jesus, but I don't think we can expect dramatic changes compared with the first meeting.
"For Benfica and Zenit this will be a decisive game, both teams need to get points, both are very eager to win. This will be a difficult match in which anything could happen. We will make every effort to earn the three points."
4.32pmBenfica coach Jorge Jesus: "This game is crucial for us. We are level on four points with Zenit. Leverkusen, apparently, are already through. We know they are capable opponents, but I believe in our team and that we can win – the team is ready.
"The players know this is a Champions League game. It is an honour for every player to play in this competition. Yes, me and Villas-Boas know each other – and the way each other's teams like to play – so we won't be able to spring many surprises, though anything can happen."
4.35pmTo give a bit more context in terms of tonight's permutations, Zenit will be out of the competition if they lose and Monaco beat Bayer Leverkusen later this evening. Meanwhile, Benfica will be packing their bags if they draw or lose and Monaco beat Leverkusen. With this being the Champions League, there is sure to be plenty of twists and turns ahead this evening.
4.38pmWhen it comes to recent form in all competitions, Benfica have the upper hand with four wins in their last four matches. Zenit have lost three and won three of their previous six games.
ZENIT: WLWLLW BENFICA: DLWWWW
4.41pmZenit forward Hulk is sure to have a few people scratching their heads tonight with his erratic style of football, but the Brazilian had a decent record against Benfica during his Porto days. He scored a total of five goals in 12 games and was on the winning team six times. AVB will be hoping that the 28-year-old is at his boisterous best for this game.
4.44pmThe bad news for Benfica is that their record in Russia is far from stellar. The Portuguese side have won just once in six attempts, with that result coming way back in 1996 against Lokomotiv Moscow. The other five meetings ended in three defeats and two draws.
4.47pmTo make matters worse for Benfica, Zenit have never lost at home to a team from Portugal. The Russians have won four and drawn two of their six matches. Jorge Jesus knows that it's going to be difficult for his side this evening, but you wouldn't put it past the wily old fox pulling something surprising out of the bag.
4.50pmPREDICTION TIME: So, how do you see this one panning out this evening? Zenit have the home advantage and a draw could keep them in the competition, while Benfica are in the better form overall and ideally need to win the game. Call us crazy, but we here at Sports Mole can see the visitors coming away with a 2-1 victory tonight.
4.55pmThe teams emerge from the tunnel as we head closer to kickoff at the Stadion Petrovski. All that's left is that rousing Champions League anthem and a few friendly handshakes before we go head first into the action. Not long now!
1 minKICKOFF! The music has been blasted out, the pre-match handshakes have been done and it will be hosts Zenit to get us underway in this vital clash in Group C. Here we go!
3 minIt's been a bright start from the home side, who are looking to get at their opponents early on. Hulk wins a free kick out on the right that the Brazilian eventually whips into a dangerous area, but he puts a bit too much on it and the ball misses Lombaerts before going out of play.
6 minCHANCE! Zenit come close to taking the lead as Hulk hammers a free kick from the edge of the box towards goal before Julio Cesar parries it. However, the goalkeeper doesn't get much on it and there is an almighty scramble that follows until the shotstopper finally gets a hold of the ball.
8 minAs you might imagine, it's brutally cold in Russia. It's all long sleeves and gloves for the players out there as they try to combat the harsh conditions. The two managers are also suitably attired for the weather, with both of them wearing big coats and gloves.
10 minYELLOW CARD! The first booking of the match goes to Benfica defender Jardel for dragging down Rondon with Zenit looking to break. That was a cynical challenge and there are no complaints from the visitors.
13 minZenit are doing all the pressing at the moment. Benfica can hardly get out of their own half. Luckily for the Portuguese side, their defence is well drilled and is doing a good job of soaking up all this pressure. The hosts launch another attack as Witsel tries to jink his way through, only for the flag to go up for an infringement.
16 minThis is better from Benfica. They're starting to pose a few questions of the Zenit defence. The visitors win a corner first of all that Lodygin flaps at before clearing, while a throw in shortly after causes a few problems before the hosts hack the ball clear.
19 minThis game has got a decent flow to it at the moment with Zenit doing most of the pressing and Benfica looking to hit them on the break. Zenit forward Hulk has impressed in particular during the opening 20 minutes or so, running at the hosts and putting in some decent deliveries from out on the right.
21 minYELLOW CARD! Another booking for Benfica now as Samaris is cautioned for chopping down Witsel. While there was not much contact there, the midfielder will now miss his side's final match in the group against Bayer Leverkusen.
22 minZENIT SUB: Bad news for Zenit as defender Lombaerts is forced off with what looks like a leg strain of some sort. Luis Neto replaces the Belgian international.
25 minBenfica coach Jorge Jesus should be satisfied with how his team have equipped themselves so far. The visitors took a while to get going, but they're now seeing a lot more of the ball in advanced positions. That said, Zenit are still looking the more dangerous when it comes to getting that all-important opening goal.
28 minZenit captain Danny does well down the left, putting two crosses into the penalty area in quick succession. His first doesn't do much to trouble the Benfica defence, though his second forces Luisao into a rushed clearance. The Zenit players are being afforded plenty of space when they get into the final third.
30 minYELLOW CARD! He's not been on the pitch for very long, but Luis Neto now goes into the book for Zenit after bringing Talisca down around 40 yards from goal.
36 minYELLOW CARDS! Benfica defender Luisao is that latest name to go into the book following a reckless challenge on Rondon. Actually, Hulk is the latest name to receive a yellow card for a foul on Perez. There's not much in the way of a rhythm to this game now, with both teams getting into a pattern of committing needless fouls.
38 minCHANCE! Benfica almost open the scoring through Salvio, who arrives at the back post to connect with a cross from the left. However, Lodygin does well to make an instinctive save that sees the ball move away from danger.
41 minBenfica are controlling the majority of possession as we head towards half time in St Petersburg. The visitors are putting together some good passes high up the pitch, keeping the Zenit defence on their toes.
43 minYELLOW CARD! Zenit defender Criscito rightly goes into the book for a nasty tackle on Salvio from behind. That was an ugly one, it has to be said.
45 minThere will be THREE MINUTES of added time...
5.52pmThe half-time whistle goes, bringing an end to a curious opening 45 minutes in St Petersburg. Zenit started the match strongly, but it was Benfica who finished in the ascendancy. However, the one defining factor in that first half was a lack of discipline from both sides. We've had a handful of bookings so far which has stopped the game getting into any sort of rhythm.
5.55pmThe liveliest player on the pitch so far has been Zenit forward Hulk, though he drifted away as the half wore on. He played a part in the home side's best chance of the half when his free kick caused all sorts of chaos in the Benfica box early on. Meanwhile, the away team's best opening fell to Salvio, whose effort at the back post was kept out by goalkeeper Lodygin.
5.59pmA reminder of the permutations for this match: Zenit will be out of the competition if they lose and Monaco beat Bayer Leverkusen later this evening. Meanwhile, Benfica will be packing their bags if they draw or lose and Monaco beat Leverkusen. With this being the Champions League, there is sure to be plenty of twists and turns ahead this evening.
6.02pmOf the two managers, it is likely to be Benfica's Jorge Jesus who is the happier after that first half. His side were far from their best, but they grew into the match as it wore on. They looked to be more like their attacking selves come the half-time whistle. AVB is sure to be pleased with how his team came flying out of the traps, though a lack of quality when it matters has been their Achilles heel.
6.05pmWhat this game has certainly lacked so far is flow. The referee was having to blow his whistle every couple of minutes at one point due to the two sides giving away a frustrating amount of free kicks. Let's hope the second half picks up in that respect.
46 minSECOND HALF UNDERWAY! The teams are out for the second half and it will be Benfica to get us back underway. Here we go!
49 minThe visitors have been the better side during these early stages of the second half, with Gaitan blasting his speculative effort on the angle high and wide. Benfica win themselves a corner soon after, though Perez's delivery from the left is cleared.
52 minBenfica are really cranking up the pressure now. Perez is in the thick of the action again as he whips a dangerous cross in from the right, only for Criscito to get to it first and hack it away. It's all hands to the pump for Zenit at the moment.
57 minZENIT SUB: That's Javi Garcia's night over. The midfielder pulls up with what looks like a hamstring injury and is replaced by Fayzulin.
60 minBenfica are dominating possession as we head into the final 30 minutes of this match. The visitors are having to be patient though because Zenit are getting plenty of bodies back in front of their penalty area. Zenit have offered very little in this second half from at attacking point of view, it must be said.
63 minCHANCE! Zenit have been up against it so far in this half, but they nearly take the lead through Hulk! Danny does all of the work, running from his own half right into the Benfica box. He tries to tee it up for his teammates, who proceeds to get the ball stuck under his feet before the visitors clear.
64 minZENIT SUB: A final change from the home side sees Ryazantsev replaced by Shatov, who is likely to provide them with more of a threat in the final third.
67 minThis game is becoming increasingly open now, with both sides pushing forward whenever they can. Credit to Zenit, they're starting to fight a bit more following a disappointing start to the second half.
69 minBENFICA SUB: The away side make a change now as Derley replaces Talisca. Just over 20 minutes left to play in St Petersburg. While a draw would be a good result for Zenit, Benfica are in need of a win.
72 minZenit get a sniff at goal when a mistake at the back allows Hulk to get the ball on the edge of the box, but a heavy touch from the Brazilian gives Benfica a chance to clear. You get the feeling that it might be an error that decides this match, should we have a winner.
75 minShatov has added a bit of a spark to the Zenit forward line since he came on, showing no fear in running at the Benfica defence. He's certainly been busy since entering the action. The hosts win a free kick about 30 yards from goal following a foul on Shatov, only for Hulk to smash the ball high and wide.
78 minBenfica create something of a half-chance as Luisao heads a free kick down at the back post, but the referee blows his whistle for an infringement with the ball pinging around the box.
79 minWe have a goal! Zenit give themselves a vital lead thanks to captain Danny! The midfielder is picked out in the box with a superbly incisive pass from Hulk before hitting a first-time finish past the goalkeeper. That came out of nowhere, a really clinical goal.
81 minBENFICA SUB: The visitors make another change as Ola John replaces Samaris. Benfica have just under nine minutes of normal time remaining to turn this around.
84 minBenfica are starting to look a bit desperate as they try to get something out of this game. They've been the better side this evening, but it's Zenit who are on course for the three points. While the Portuguese have dominated possession and played the better football, it's their lack of finishing that could well have cost them.
87 minZenit are effectively camped just outside their own penalty box at the moment in the hope of protecting their lead. The Russians know just how precious that goal from Danny could be and are not willing to risk it for anything.
90 minThere will be THREE MINUTES of added time. Surely Zenit aren't going to throw it away now?
6.58pmZenit keep their hopes of reaching the last 16 alive with a 1-0 win over Benfica, who are out of the Champions League. It was far from a classic, but the Russians did what they needed to do to stay in the competition. Danny scored the only goal of the game with 11 minutes remaining - how vital could it be come the end of the group stage?
7.00pmThat's all from our live text coverage of tonight's match, but don't forget that you can keep up to date with all of the reaction from both camps right here on Sports Mole. Thanks for your company, we hope to see you again soon. Goodbye!