Man United secure opening win; Liverpool and Man City take the field tonight.
Liverpool begin their Group D campaign without the injured Virgil Van Dijk away to Ajax.
Their first choice centre-back needs a knee operation after last Saturday's Merseyside derby.
It's been suggested Van Dijk's absence will derail the team and midfielder Georginio Wijnaldum says they'll certainly miss his qualities:
Manchester City, still looking for their first-ever European Cup, begin their Group C campaign with the visit of Porto to the Etihad.
Boss Pep Guardiola admits he still feels responsible for their Champions League quarter-final exit last season, after suffering a shock defeat to Lyon in August.
Guardiola says it felt like they were close but just fell short:
Manchester United got their Champions League campaign off to a winning start last night.
They beat Paris Saint Germain, 2-1 in the French capital thanks to a Bruno Fernandes re-taken penalty and Marcus Rashford winner.
Manager Ole Gunnar Solskjaer was delighted with his players' performances - particularly young defender Axel Tuanzebe:
Chelsea boss Frank Lampard says it feels good not to have conceded a goal in their opening Champions League group game.
They drew nil-nil with Sevilla at Stamford Bridge.
After throwing away the lead twice against Southampton in the Premier League at the weekend, Lampard was pleased with the response:
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