UEFA Champions League round of 16 by numbers

Halfway through the first-leg stage of the UEFA Champions League round of 16, UEFA.com looks ahead to next week's four remaining ties and explains that, while home has many comforts for SSC Napoli, it is a different story at Stade Vélodrome. We also reveal FC Basel 1893's inside man and an unbeaten record to hearten PFC CSKA Moskva for the visit of Real Madrid CF.

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Both Olympique de Marseille and FC Internazionale Milano suffered two home defeats in the group stage; each collected only three points at home compared with seven on their travels.

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Basel will not have far to look for inside information on FC Bayern München – coach Heiko Vogel spent nine years in the German giants' youth department from 1998 to 2007. That period featured spells overseeing the Under-10, U13, U15 and U17 teams, with Vogel coaching Thomas Müller, Philipp Lahm and Diego Contento.

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Less happily for the Swiss side, Bastian Schweinsteiger has scored four times in his last three trips to St. Jakob-Park. The midfielder got both goals as Bayern came from behind to win 2-1 at Basel in last season's group stage, and found the net in successive games there at UEFA EURO 2008 – against Portugal in the quarter-finals and Turkey in the semi-finals.

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Basel conceded ten goals in the group phase – more than any other club to reach the round of 16 – although they are 13 matches unbeaten in all competitions, winning nine and drawing four since their 2-0 home defeat by SL Benfica on 18 October.

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Real Madrid won all six group games (just the fifth side to do so since the advent of the UEFA Champions League) and have recorded victories on their last two Russian assignments. Before that first win, at FC Lokomotiv Moskva in the 2002/03 second group stage, they had drawn three and lost four – including three in succession – of their fixtures in Russia. They are unlikely to have things their own way against a CSKA Moskva outfit unbeaten in five matches, home and away, against Spanish opposition.

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Chelsea FC also face an exacting first leg at Napoli, where fellow Premier League powerhouses Manchester City FC lost earlier this term. Since returning to continental competition after a 13-year absence in 2008, Napoli have gone 11 games undefeated at the Stadio San Paolo. The last foreign club to prevail in Naples were Eintracht Frankfurt in December 1994, while Chelsea have triumphed only once in seven visits to Italy.

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Having suffered their heaviest European reversal in succumbing 4-0 at AC Milan, Arsenal FC have to do what just three teams have previously managed in UEFA competition – recover a four-goal first-leg deficit. Real Madrid lost 5-1 at VfL Borussia Mönchengladbach in the 1985/86 UEFA Cup third round but won the return 4-0, while Leixões SC (v FC La Chaux-de-Fonds, 1961/62 European Cup Winners' Cup first round) and FK Partizan (v Queens Park Rangers FC, 1984/85 UEFA Cup second round) overturned 6-2 away losses with 5-0 and 4-0 home victories respectively. All three sides, however, had the benefit of away goals – something Arsenal cannot claim.

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Should there be any danger of complacency in the Milan camp, a reminder of their 2003/04 quarter-final against RC Deportivo La Coruña may be in order. The Rossoneri strolled the first leg 4-1 at San Siro only to go down 4-0 in Spain – the biggest first-leg advantage to be overhauled in the UEFA Champions League era.

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Arsenal are not the only club with history against them. A 3-1 home defeat by FC Barcelona means Bayer 04 Leverkusen must break new ground. The German team have lost all seven ties in which they have suffered a first-leg home reverse, whereas Barcelona have progressed on 31 of the 33 occasions they won away first. They once surrendered a two-goal cushion, however: a 4-2 success at FC Metz preceding a 4-1 home defeat in the 1984/85 Cup Winners' Cup first round.

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Olympique Lyonnais have more grounds for optimism – they have triumphed in all five UEFA ties in which they have won the first leg 1-0 at home; a margin they achieved against APOEL FC thanks to Alexandre Lacazette's second-half strike. The Cypriot champions, though, have already hurdled one 1-0 away defeat this season, overcoming Wisła Kraków 3-1 in the second leg of their play-off tie.

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Zlatan Ibrahimović scored for the fifth consecutive UEFA Champions League game with his late penalty against Arsenal – Gunners striker Marouane Chamakh holds the competition record having found the net in six straight matches for FC Girondins de Bordeaux and Arsenal in 2010.