After the opening four first legs saw four away wins, UEFA.com looks at the omens for the remaining ties, with history favouring Manchester United FC and Real Madrid CF.
FC Zenit v Borussia Dortmund
• Zenit qualified for the knockout phase for just the second time in their history with six points, a record low tally for a UEFA Champions League group stage. They drew all three home matches: 0-0 with FK Austria Wien and 1-1 against both FC Porto and Club Atlético de Madrid.
Olympiacos FC v Manchester United FC
• United have won each of the clubs' four previous encounters, triumphing 2-0 away and 3-0 at home in the 2001/02 first group stage and 4-0 in Manchester and 3-2 in Piraeus at the same juncture of the following campaign. Ryan Giggs, who has appeared in all four games, scored in both Old Trafford matches.
FC Schalke 04 v Real Madrid CF
• Madrid have prevailed just once in 25 previous visits to German opposition, losing 18 times, including a 4-1 reverse at Borussia Dortmund in last term's semi-final first leg which set up a 4-3 aggregate defeat. The solitary victory was a 3-2 success at Leverkusen in 2000/01.
Galatasaray AŞ v Chelsea FC
• Galatasaray striker Didier Drogba was at Chelsea between 2004 and 2012 – playing under José Mourinho from June 2004 to September 2007 – and scored 100 goals in 226 league outings. He lifted three Premier League titles, four FA Cups and two League Cups while his last kick for the club was the clinching penalty in the 2012 UEFA Champions League final shoot-out against FC Bayern München.