The Champions League league phase intensifies this week with a packed schedule of high-stakes fixtures. Wednesday's highlight features a titanic clash at the Etihad Stadium between Manchester City and two-time defending champions Paris Saint-Germain. Meanwhile, Jose Mourinho returns to face his former club, AS Roma, in an electric atmosphere at the Stadio Olimpico. Tuesday's action sees Atletico Madrid taking on a struggling Manchester United, and an in-form Barcelona squad, led by Lamine Yamal, heading to Istanbul to face Galatasaray. Other key fixtures include Arsenal hosting Lille and Bayern Munich traveling to Norway, as Europe's top clubs look to secure their footing in the tournament.