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TUESDAY'S MATCHES
Ronaldo eyes 100 European goals
Cristiano Ronaldo has a record collection like few others, but becoming the first player to score 100 goals in European club competition would be one of his most impressive personal milestones. The 31-year-old needs just two more to reach a century in UEFA club competition. Legia Warszawa's -8 goal difference from their first two Group F fixtures does not bode well for them, though the match does fall exactly 21 years to the day since the Polish side's last UEFA Champions League triumph.
Real Madrid v Legia

Akinfeev's ten-year wait
It is coming up to ten years since Igor Akinfeev last managed a clean sheet in the UEFA Champions League. Even the most successful attacking teams are founded on the bedrock of a sound defence – Real Madrid kept their opponents out 11 times out of 13 en route to the title last season. CSKA would dearly like to rediscover the knack, and they weren't too far off last time out against Tottenham. Could the end be nigh? It won't be easy: Group E opponents Monaco began October with their biggest-ever league away win.
CSKA Moskva v Monaco

The longest unbeaten run
København's confidence should be sky-high as the Danish title holders visit the English Midlands, befitting the team with the longest unbeaten run – comprising 23 games dating back to 22 May – of any side in this season's UEFA Champions League. That sequence includes eight European matches this term, yet could be severely tested by the Group G leaders who have compelling reasons of their own to believe. Leicester's last 22 home fixtures have produced just two defeats, contrasted with 13 victories, and the Foxes can also point to the fact FCK have never won in England.
Leicester v København

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Sporting have their work cut out
Having won only two of their 12 previous home games against German opposition (W2 D5 L5) – a record that includes their heaviest ever European home defeat, 5-0 against Bayern München in February 2009 – Sporting CP face a huge task to stop free-scoring Borussia Dortmund. "The draw [between Dortmund and Real Madrid on matchday two] left the group even and now we have to try to get points against Dortmund," Bryan Ruiz told UEFA.com after the 2-0 victory against Legia Warsawa.
Sporting v Borussia Dortmund

WEDNESDAY'S MATCHES
Napoli one win from history
Napoli are on the verge of UEFA Champions League history. If the Partenopei can overcome Beşiktaş, and Dynamo Kyiv draw with Benfica in the other Group B fixture, the Serie A side will become the first team ever to progress from a UEFA Champions League group with three matches to spare. The omens are good, for Beşiktaş are yet to win in 11 attempts (D2 L9) against Italian opponents.
Napoli v Beşiktaş

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Guardiola's return to Barcelona
Josep Guardiola makes a Group C return to the club where he made his name. Guardiola, who "has to be thanked for everything he has done for the club" according to Barcelona centre-back Gerard Piqué, lifted six league titles and a European Cup as a player with the Azulgrana before amassing 14 trophies – including two UEFA Champions Leagues – as a coach there. His only previous Camp Nou homecoming, with Bayern München in the 2014/15 semi-finals, ended in a 3-0 defeat.
Barcelona v Manchester City

Basel's trip to fortress Paris
All the statistical evidence suggests a comfortable evening at home for Unai Emery's men. Not only are Paris the early joint leaders of Group A, they also have the assurance of a 41-game home run, spanning ten years, in which they have lost only once at the Parc des Princes. And that defeat came against 2015 champions-elect Barcelona. What's more, and what adds yet more metres to the metaphorical mountain ahead of Basel, is that the Swiss champions have never won in France.
Paris v Basel