Only two more rounds of the group stage of the Champions League remain, and for quite a few teams, that means the margin for error is slim to none.

Over the final two match days, there are a number of important games that will determine how things shake out. Several of Europe’s elite, like Barcelona and Bayern Munich, who boast the tournament’s leading scorers in Lionel Messi and Mario Gomez, are in favorable positions heading into their last two matches, but there are also a couple of notable few who still have some work to do to keep alive their quest to be the best. Champions League betting odds will favor the big names, without a doubt, but don’t discount the possibility of an upset or two… or more.

Group A

Bayern Munich are in the driver’s seat in Group A, and if things go according to form (and theirs has been very, very good this season), they’ll clinch at least a place in the round of 16 with a home win over disappointing Villarreal in their next match.

While Napoli are still mathematically in the hunt to win the group, Manchester City are the only real challenger to Bayern’s place at the top. However, City’s place in the final 16 is far from assured, because while they hold the edge over Napoli, that could change next week when the Premier League leaders visit the San Paolo.

Napoli notched an impressive 1-1 draw in Manchester, and not only would they end City’s hopes of winning the group if they go one better at home, but they would be favored to finish second. Napoli finish away to Villarreal, who won’t be playing for anything more than a spoiler role, while City host Bayern, who won’t be in the business of doing any favors even if they’ve got top spot all wrapped up already.

Group B

Inter may still barely have their heads above water in Serie A after digging themselves an early hole, but they’ve rounded into form in Europe and are set to go through to the round of 16 as group winners.

It’s only fitting that they could and should wrap up the group in their penultimate match away to Trabzonspor to show just how removed they are from September’s shock home defeat to the Turkish side, even if their domestic form is still lagging.

Trabzonspor may have picked up only two points since their stunning success at the San Siro, but they still have a chance to qualify for the round of 16. However, CSKA Moscow have a definite edge as of now, and a home win over bottom side Lille, combined with an Inter win in Turkey, will render the Russian’s side final match in Milan meaningless.

However, even if those results occur, Lille’s home tie against Trabzonspor on the final matchday would still be of great importance, as Lille, as surprisingly underwhelming as they’ve been in the group stage, would claim the Europa League consolation prize with a win. And if the reigning French champions can manage a positive result in Moscow, which won’t be easy, a win over Trabzonspor could put them in line for something more, if the result in Milan is in their favor.

Group C

Despite not looking particularly convincing thus far in the group stage, Manchester United find themselves in a familiar position as group favourites going into crunch time, which is usually when we see them at their best.

A win and a draw will do the trick, and you’d have to fancy them to do at least that, if not win both matches, but the road could be tricky. Next Tuesday, they host Benfica, who have yet to lose in any competition this season (19 matches, to date). Then United finish up with a trip to Basel, who stunningly overturned a 2-0 halftime deficit in a 3-3 draw at Old Trafford in September.

If Basel can win in Romania against Otelul Galati next week, they’ll go into their rematch with United still with a chance to win the group, so United won’t be able to sleepwalk through that one.

While Basel could go into that match with a chance to reach the round of 16 and reach it as group winners, Benfica are well-placed to advance even if they lose at Old Trafford. Their last match is in Lisbon against Otelul, who could well end up without a point to show for all of the toughness they’ve displayed to this point.

Considering how difficult they have been to put away, Basel will be making a monumental mistake if they go into next week’s tie with the resilient Romanians already looking ahead to their showdown with United.

Group D

Real Madrid, with four wins in four matches, have already secured a place in the round of 16, and Jose Mourinho’s side will seal top spot in Group D with a win next week at the Santiago Bernabeu against Dinamo Zagreb, who haven’t scored a goal yet, much less picked up a point.

But it looks likely that second spot will come down to the final match-day, and even though Ajax have the edge right now, it might not be a stretch to say that Lyon should be considered favourites to join Real in the knock-outs.

Lyon host Ajax next week, and with their impressive run of eight straight knock-out round appearances on the line, you’d have to favor the likelihood of them taking care of business in this crucial clash, especially when you also consider how formidable they are at home in Europe. In fact, since making their Champions League debut in the 2000/01 season, Lyon are 22-8-8 in group stage play, with five of those defeats coming in their first three appearances.

In the final round of matches, Ajax host Real, who will be eyeing the rare feat of a perfect group stage record, while Lyon will be away to Dinamo Zagreb, which won’t be an easy tie but is a markedly more favorable one than the one Ajax have to deal with.

Group E

Like Real Madrid and Lyon, Chelsea haven’t failed to make the Champions League round of 16 since the format changed in 2003. That looks almost certain to continue, but will the Blues go through as group winners as they’re accustomed to?

That’s not a certainty, as they face a testy trip to Bayer Leverkusen before finishing up at Stamford Bridge against Valencia, who, provided they take care of business at home against Genk next week, will head to London still with a chance to reach the last 16.

As of now, Leverkusen are the favorites to join Chelsea in moving on, but could they be made to rue being unable to close out positive results in away matches against Chelsea (0-0 until the 67th minute) and Valencia (1-0 Leverkusen until the 65th)?

Leverkusen have been pretty up and down this season, but if the right Leverkusen side shows up against Chelsea next week, they’ll head into a very winnable finale away to Genk poised to take top spot. To nab it wouldn’t be a small feat, even if Chelsea are still trying to find their feet under Andre Villas-Boas.

Group F

Unless both sides absolutely fall flat in their last two matches, Arsenal and Marseille will be on their way to the round of 16, likely with the Gunners as group winners and the French side in second.

Arsene Wenger was made to rue starting Robin van Persie from the bench in their goalless home draw with Marseille last time out, with RVP not coming on until the 62nd in that match. But it’s highly unlikely Wenger will leave his best player – and one of the hottest scorers in the game right now – in either of Arsenal’s last two matches, a visit from Dortmund and an away tie against Olympiakos.

The Dortmund tie will be a real tests, since the reigning German champions are playing very well as of late and will be doing everything they can to maintain their slim round of 16 hopes, with Marseille coming to Signal Iduna Park in their group finale. A Dortmund win in that one is a good bet, with how strong – and I mean strong – Dortmund are at home.

But Dortmund will need to win at the Emirates next week for something more than a Europa League place to be on the line when Marseille come to town next month.

As for Olympiakos, they still technically have a chance to win the group, but the best they’re going to do, barring a miracle, is third. If it happens to come down to a head-to-head tiebreaker, the Greek champions would have the edge, though Dortmund certainly aren’t resigning themselves to a place in the Europa League just yet.

Group G

Bayern Munich, Inter Milan, Manchester United, Real Madrid, Chelsea, Arsenal, APOEL Nicosia, Barcelona. Which one of these is not like the rest?

The favorites are sitting atop every group except for Group G, where an unfancied side from Cyprus has well and truly upset the applecart thus far with a surprising and unexpected unbeaten run.

But can they seal the deal and join the best of the best in the last 16? Zenit might be poised to take top spot from them, as they host the group leaders next week, but even with a defeat in Russia, APOEL will have reason to feel confident about their chances to win the group, as they host Shakhtar in the final round of matches, whereas Zenit are away to Porto.

For what it’s worth, don’t sleep on Porto, as disappointing as they’ve been to this point. They’re still a very talented bunch, and an away win against Shakhtar could turn the tide in their favor. It looks like two wins are a must for Porto, which won’t be easy, but if they can produce two quality performances, those two wins – and perhaps a group win – could be on the cards.

Amazingly enough though, Shakhtar can’t be dismissed as a threat either. If they beat Porto, they’ll be in a position where they could wind up second with a win over APOEL… who could end up dropping into the Europa League if they lose both remaining matches.

But unlike most of the other groups, it’s absolutely impossible to predict what will happen in Group G, due to the several surprising results we’ve seen to this point.

Group H

It’s already been confirmed that Barcelona and AC Milan will be the top two from this group, but what will the final order be?

Milan allowed a second-half equalizer in a 1-1 draw against BATE Borisov in their last group match, which means that they’ll need to beat Barcelona at the San Siro next week in order to have a chance to win the group.

That’s certainly possible, since they did draw 2-2 in Nou Camp after all, but if the best they can manage is a draw, they’ll not only need to defeat Viktoria Plzen in their final match, they’ll need to hope that BATE miraculously pulls off a win at Barca. So, in other words, AC Milan need to win next week.

Wouldn’t it be fitting if Zlatan Ibrahimovic, lover of all things Barcelona, scored the winning goal for AC Milan?

As for third and the Europa League spot that comes with it, BATE will definitely claim it if they beat Viktoria Plzen next week in Minsk, but avoiding defeat will all but wrap it up, unless the Czech side somehow pulled the upset and defeated AC Milan in their group finale in Prague. Anything can happen, but…