Group E (FC Basel 1893 v FC Schalke 04; FC Steaua Bucureşti v Chelsea FC)
• Basel and Schalke met in the 2004/05 UEFA Cup group stage, drawing 1-1 in Gelsenkirchen on 21 October. Basel subsitute Matías Delgado scored a late free-kick to secure a point for the visitors, who also included the Degen brothers. Levan Kobiashvili had put the home team ahead.
• Last season's Steaua win against Chelsea came in the UEFA Europa League round of 16 when Raul Rusescu's first-half penalty put the 2012 UEFA Champions League winners on the back foot. Juan Mata levelled the overall scores at Stamford Bridge and, though Vlad Chiricheş restored Steaua's aggregate advantage, John Terry and Fernando Torres struck to take the Londoners through.
Group F (Borussia Dortmund v Olympique de Marseille; Arsenal FC v SSC Napoli)
• Dortmund and OM went head-to-head in the UEFA Champions League group stage two years ago, with Marseille prevailing 3-0 at home and 3-2 away.
• Arsenal have frustrating memories of their last contest with a Serie A side. Facing AC Milan in the 2011/12 UEFA Champions League round of 16, they looked out of it after losing 4-0 away but responded in style in the return. Laurent Koscielny and Tomáš Rosický scored inside the first 30 minutes, but the eventual 3-0 win was not enough.
Group G (FC Zenit v FK Austria Wien; FC Porto v Club Atlético de Madrid)
• Zenit are tackling Austrian opponents for only the third time, and their two previous encounters came against the same club, ASKÖ Pasching – later renamed SK Austria Kärnten – in successive campaigns: 2004/05 and 2005/06.
• Porto won all four home fixtures in last season's UEFA Champions League, scoring eight goals and conceding just two.
Group H (AFC Ajax v AC Milan; Celtic FC v FC Barcelona)
• Ajax claimed four points off Milan in the 2010/11 group stage. Then as now they met in Amsterdam on matchday two, with Milan's Zlatan Ibrahimović registering against his old club to cancel out Mounir El Hamdaoui's goal in a 1-1 draw. Demy de Zeeuw and Toby Alderweireld gave Ajax a 2-0 victory in the return.
• Barcelona's record in Scotland is W2 D1 L3. They achieved an identical record on their travels in last term's UEFA Champions League, but did not win any of their three away games in the knockout rounds.
Group A (FC Shakhtar Donetsk v Manchester United FC; Bayer 04 Leverkusen v Real Sociedad de Fútbol)
• Shakhtar have won all three previous UEFA Champions League fixtures against English visitors to Donetsk, with earlier successes against Arsenal in the 2000/01 first group stage (3-0) and 2010/11 group stage (2-1). Overall their home form against Premier League sides is W4 D1 L0.
• Leverkusen's most famous European nights have come against Spanish teams. They lost the 2002 UEFA Champions League final 2-1 against Real Madrid CF in Glasgow, but beat RCD Espanyol in a dramatic two-legged UEFA Cup final in 1988.
Group B (Juventus v Galatasaray AŞ; Real Madrid CF v FC København)
• Juventus and Galatasaray have faced each other in two UEFA Champions League group stages, most recently in 2003/04 when Alessandro Del Piero scored twice in Turin to earn the Bianconeri a 2-1 victory after Hakan Sükür had equalised.
• During his first spell as København coach, Ståle Solbakken oversaw four European matches against Spanish opposition. His statistics against Valencia CF, Barcelona and Atlético read W0 D2 L2.
Group C (Paris Saint-Germain FC v SL Benfica; RSC Anderlecht v Olympiacos FC)
• PSG are unbeaten in all six home games against Portuguese opponents, winning four and drawing two. The last meeting came in the 2012/13 UEFA Champions League group stage when they beat Porto 2-1 to clinch first place in the section.
• The last time the Anderlecht-Olympiacos fixture was played was autumn 1974 in the European Champion Clubs' Cup second round. Anderlecht were 5-1 home winners but had to withstand an almighty second-leg scare in Patras as Maik Galakos hit a hat-trick for Olympiacos, who nevertheless bowed out after only managing a 3-0 success.
Group D (PFC CSKA Moskva v FC Viktoria Plzeň; Manchester City FC v FC Bayern München)
• Since losing their opening away fixture of last season's UEFA Europa League group phase at Atlético, Plzeň have put together a run of five victories and two draws on the road.
• Besides their Wembley final triumph in May, Bayern also won at Arsenal in last term's competition, Toni Kroos, Thomas Müller and Mario Mandžukić handing them a 3-1 success in the round of 16. They lost the second leg 2-0 but advanced on away goals.
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