A total of nine players are just one yellow card away from being suspended for the Champions League final ahead of the semi-final second legs.
For holders Bayern Munich, striker Mario Mandzukic is at risk of a ban as they look to overturn a 1-0 deficit to Real Madrid from the first game.
The Spanish giants have three players who will miss the Lisbon final should they pick up a booking in Germany. Sergio Ramos, Xabi Alonso and Asier Illarramendi will all need to be wary of incurring the wrath of referee Pedro Proenca.
Chelsea host Atletico Madrid in the second of the semi-final second legs with two Brazilians walking a disciplinary tightrope. David Luiz - who could well feature in central midfield, given that Frank Lampard and John Obi Mikel are suspended from the clash - is just a booking away from being banned himself, while attacking midfielder Willian is also at risk.
Atletico, like rivals Real, have three players who could potentially miss the final: defenders Emiliano Insua and Juanfran, as well as midfield star Koke. Captain Gabi is banned from the semi-final second leg.
Bayern face Real Madrid on Tuesday at the Allianz Arena at 19.45BST, with Chelsea taking on Atletico on Wednesday.