European action takes center stage next week, as next week will mark the halfway point of the group stage of the Champions League.

While there is much to be decided between now and the last round of group stage fixtures in early December, several teams, including a couple of Europeís elite, are already facing matches that they can ill afford to lose or even draw if their ambitions are to stay intact.

Group A: Manchester City v. Villarreal

Manchester City havenít had the start to life among the best of the best in Europe as many expected they would. City have opened Champions League play with a home draw against Napoli and a defeat at Bayern Munich, and coming into Tuesday nightís meeting with Villarreal, they sit third in the Group A table, five points behind Bayern, three behind Napoli, and level on points with next weekës opposition.

Itís fair to say that this is a must-win match for both sides with respect to their round of 16 hopes, especially if Napoli happen to beat Bayern. Of course, the pressureís much more on City than on Villarreal, given that theyíre at home and considering the sky-high expectations facing them this season. Failing to make the round of 16 would be considered a serious disappointment for Roberto Manciniís side, even with Group A being the toughest group in the competition, but a win against Villarreal will throw them right back into the thick of things.

If you support City or Villarreal, you wonít want to miss this match, and Manchester City v. Villarreal tickets are available at TicketBis from £130.81.

Group B: Lille v. Inter Milan

Inter also havenít had the start that they were expected to domestically and continentally, but thereís plenty of time left to right the ship domestically, and they still look a good bet to make the Champions League round of 16 yet again.

However, if they want to win the group, a win at Lille next Tuesday night would be ideal, as it would likely move Claudio Ranieriís side into top spot in Group B, as current group leaders Trabzonspor, who scored a shock win at the San Siro last month, are away to CSKA Moscow.

But if Lille can hold serve at home, it would be a big boost to their hopes of making the round of 16 in the Champions League, as they currently sit in third on two points, two behind Trabzonspor and one behind Inter. To do that though, theyíll have to do a far better job of holding a lead than they did in their first two matches, as they surrendered a two-goal lead in the final 20 minutes in a home draw against CSKA Moscow and allowed a late equalizer in a 1-1 draw at Trabzonspor.

Group F: Marseille v. Arsenal

Finishing second in their group last season landed Arsenal a tie against eventual champions Barcelona in the round of 16, and the Gunners will be keen to avoid putting themselves in position to face such a tough matchup this season if they reach the knockout stage.

If they can put their away demons behind them and pick up a win at Marseille next Wednesday, theyíll move ahead of Marseille into top spot in Group F. Currently, Marseille top the group with maximum points from two matches, while Arsenal are second on four.

It looks like those two will nab the top two spots in the group, though Borussia Dortmund will move back into the mix if they make the most of two winnable matches against Olympiakos. With that potential threat in mind, along with the desire to avoid say, Barcelona or Real Madrid in the round of 16, a win at Marseille would be an ideal result for Arsenal. At the same time, if Marseille can make it three wins from three, theyíll head into next monthís rematch at the Emirates knowing that a positive result could all but seal top spot.

UEFA Champions League Tickets at TicketBis

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