Welcome to Hellas
With Juan Mata cup-tied, Ashley Young started for Manchester United at Olympiakos.
United were off key and they were punished in the first-half by Chori Dominguez, whose cute flick gave Olympiakos the lead.
Things went from bad to worse for United when Arsenal loanee Joel Campbell doubled Olympiakos' advantage in the second half.
Manchester United's defence was all at sea as they crashed to their first ever defeat to Greek opposition.
David Moyes tries to come to terms with his side's poor performance in Greece.
Henrikh Mkhitaryan gave Borussia Dortmund the perfect start against Zenit, scoring after four minutes. Marco Reus added a second a minute later.
Hulk had missed his last three UCL penalties but netted from the spot to give Zenit hope at 3-2 down.
Robert Lewandowski scored his second and his side's fourth to put Dortmund out of sight in St Petersburg, with Juergen Klopp's men now on the brink of the quarterfinals.