Real Madrid, Barcelona, Sevilla, Juventus, Roma, Bayern, Manchester City, and Liverpool will all be seeking their places in the Champions League semi-finals over the next week. Injuries, suspensions, players returning, and those walking a suspension tightrope will all have an effect on who goes through the last four.
Bayern are one of the teams with the most players absent through injury (Neuer and Coman), with Arturo Vidal and Juan Bernát back in training after missing the 6-0 thrashing of Dortmund at the weekend. The Bundesliga leaders also have five players who will miss the second leg if they receive a yellow card in the first, including Robert Lewandowski.
Juventus also have notable absentees: Mario Mandzukic is out while Federico Bernadeschi and Juan Cuadrado have just returned after injury, the latter making a substitute appearance against Milan at the weekend. Both Miralem Pjanic and Medhi Benatia are suspended.
Manchester City are unsure whether Sergio Agüero will be available while Bejamin Mendy is out and John Stones suffered a knock to the head at the weekend. Danilo, Gundogan and Fernandinho are one yellow away from a one-match ban.
Liverpool also have their issues. Lallana and Joe Gomez are definitely out while Emre Can is a doubt and Moreno and Henderson a yellow away from suspension.
Of the Spanish teams, Real Madrid go into to the last-eight match-ups in the best shape. Zinedine Zidane has a full squad at his disposal apart from Nacho, who suffered the first injury of his senior career during Real's 3-0 win over Las Palmas. The only player one booking away from a suspension is, inevitably, Sergio Ramos.
Barcelona are slightly worse off. Sergi Roberto is close to suspension, and Coutinho is cup-tied having already played for Liverpool in the Champions League this year. Ernesto Valverde will have Semedo, Iniesta, and Alba available. Sergio Busquets doubtful after he broke his foot against Chelsea - the Spain international is back in training but did not feature at the weekend against Sevilla - while Lucas Digne is struggling with a thigh injury.
For Vincenzo Montella's side, Escudero and Mercado will be teetering along the proverbial tightrope.
Roma's Radja Nainggolan is a doubt, while Cengiz Ünder and Lorenzo Pellegrini face late fitness tests.
Champions League injuries and suspensions
Back from injury: Robben, Thiago, Vidal, Bernat
Injured: Neuer, Coman
One yellow from suspension: Kimmich, Lewandowski, Rudy, Tolisso, Boateng
Back from injury: Delph, Sterling
Doubts: Agüero, Stones
One yellow from suspension: Danilo, Gundogan, Fernandinho
Back from injury: Clyne, Wijnaldum
Injured: Lallana, Gomez, Can
One yellow from suspension: Alberto Moreno, Henderson
Back from injury: Bernardeschi, Cuadrado
One yellow from suspension: Bentancur
Suspended: Pjanic, Benatia.
Doubts: Nainggolan, Ünder, Pellegrini
One yellow from suspension: Perotti
Back from injury: -
One yellow from suspension: Ramos
Back from injury: Semedo, Denis Suárez
One yellow from suspension: Sergi Roberto
Back from injury: Navas, Corchia
One yellow from suspension: Escudero, Mercado