Your ultimate Champions League guide: Which teams are flying and where are the potential upsets?

Just 59 days after Bayern Munich lifted the trophy in Lisbon, the Champions League is back as we prepare for the start of the group stages. Just 59 days after Bayern won the Champions League, the group stages are back once more GROUP A - THE TEAMS Bayern Munich Atletico Madrid Red Bull Salzburg Lokomotiv Moscow Group A Who's flying domestically? Real Madrid stuttered to a woeful defeat at the hands of Cadiz and will be desperate to recover MATCHDAY ONE FIXTURES Real Madrid vs Shakhtar Donetsk, Wednesday night 5:55pm Inter Milan vs Borussia M'gladbach, Wednesday night 8pm The big stars At Real Madrid, the big names to watch out for are of course the likes of Karim Benzema, Vinicius and Sergio Ramos, while Inter Milan's Romelu Lukaku continues to impress since leaving Manchester United. Pep Guardiola's Manchester City will be confident they can top their group this season MATCHDAY ONE FIXTURES Manchester City vs FC Porto, Wednesday 8pm Olympiacos vs Marseille, Wednesday 8pm The big stars Again, perhaps unsurprisingly, the biggest names in Group C come at Manchester City, with the likes of Raheem Sterling, Kevin De Bruyne and Sergio Aguero all ready to line up in Europe's premier competition this week. Juventus' stars train this week as they prepare for their opening Champions League fixture MATCHDAY ONE FIXTURES Dynamo Kiev vs Juventus, Tuesday 5:55pm Barcelona vs Ferencvaros, Tuesday 8pm The big stars This group has arguably the biggest names in world football, with Juventus lining up with the likes of Cristiano Ronaldo, Paulo Dybala and Matthijs de Ligt, while Barcelona have Lionel Messi, Antoine Griezmann and Ansu Fati.