The draw for the UEFA Champions League last 16 takes place in Nyon, Switzerland today. Here PA Sport looks at the clubs involved.
Atletico Madrid
Who: Runners-up to rivals Real Madrid in the 2014 final.
How: Advanced as winners of Group A, with one defeat.
Possible opponents: Basle, Bayer Leverkusen, Arsenal, Manchester City, Paris St Germain, Schalke, Shakhtar Donetsk.
Arsenal
Who: Perennial knockout participants. Can the FA Cup winners go further than the first knockout round?
How: Runners-up in Group D behind Borussia Dortmund.
Possible opponents: Atletico Madrid, Real Madrid, Monaco, Bayern Munich, Barcelona, Porto.
Barcelona
Who: Four-time winners, with three wins in the last 10 seasons.
How: Won five of their six games to top Group F ahead of PSG.
Possible opponents: Juventus, Basle, B. Leverkusen, Arsenal, Man. City, Schalke, S. Donetsk.
Basel
Who: The Swiss champions have beaten Manchester United, Tottenham and Chelsea in recent seasons.
How: Advanced ahead of Liverpool behind Real in Group B.
Possible opponents: A. Madrid, Monaco, B. Dortmund, B. Munich, Barcelona, Chelsea, Porto.
Bayer Leverkusen
Who: The Germans finished Champions League runners-up in 2002.
How: Claimed the runners-up spot in Group C behind Monaco.
Possible opponents: Atletico Madrid, Real Madrid, Barcelona, Chelsea, Porto.
Bayern Munich
Who: Won the competition for the fifth time in 2013.
How: Claimed Group E ahead of Manchester City, who inflicted their only loss.
Possible opponents: Juventus, Basle, Arsenal, Paris St Germain, Shakhtar Donetsk.
Borussia Dortmund
Who: The 1997 winners and 2013 runners-up are toiling in the Bundesliga this term.
How: Despite their domestic troubles, won Group D ahead of Arsenal.
Possible opponents: Juventus, Basle, Manchester City, Paris St Germain, Shakhtar Donetsk.
Chelsea
Who: The first London club to win the tournament, in 2012.
How: Strolled through Group G unbeaten, scoring a tournament-high 17 goals.
Possible opponents: Juventus, Basle, B. Leverkusen, Paris SG, Shakhtar Donetsk.
Juventus
Who: The 1996 winners have not made the last four since 2003.
How: Runners-up to Atletico in Group A.
Possible opponents: R. Madrid, Monaco, B. Dortmund, B. Munich, Barcelona, Chelsea, Porto.
Manchester City
Who: The English champions whose continental jitters meant they left it late to advance.
How: Beat Roma away to follow Bayern into the last 16.
Possible opponents: Atletico Madrid, Real Madrid, Monaco, Borussia Dortmund, Barcelona, Porto.
Monaco
Who: The Ligue 1 club were runners-up in 2004.
How: Conceded just one goal in winning Group C.
Possible opponents: Juventus, Basle, Arsenal, Manchester City, Schalke, Shakhtar Donetsk.
Paris St Germain
Who: The rich Parisiens have never won the European Cup.
How: Finished runners-up in Group F after being beaten by Barca in the final match.
Possible opponents: Atletico Madrid, Real Madrid, Borussia Dortmund, Bayern Munich, Chelsea, Porto.
Porto
Who: Winners in 2004 under Jose Mourinho, now Chelsea boss, and also in 1987.
How: Claimed victory in Group H ahead of Shakhtar.
Possible opponents: Juventus, Basle, Bayer Leverkusen, Arsenal, Manchester City, PSG, Schalke.
Real Madrid
Who: The 10-time winners and defending champions.
How: Secured a 100 per cent record from Group B, finishing 11 points clear of Basle.
Possible opponents: Juventus, B. Leverkusen, Arsenal, Man. City, PSG, Schalke, Shakhtar Donetsk.
Schalke
Who: Managed by Roberto Di Matteo, a 2012 Champions League winner with Chelsea, but scraped through.
How: Overtook Sporting Lisbon with victory over Maribor in their final Group G match.
Possible opponents: Atletico Madrid, Real Madrid, Monaco, Barcelona, Porto.
Shakhtar Donetsk
Who: Ukraine champions and 2011 quarter-finalists.
How: Striker Luiz Adriano scored nine Group H goals as Shakhtar finished runners-up to Porto.
Possible opponents: A. Madrid, R. Madrid, Monaco, Dortmund, Bayern, Barcelona, Chelsea.