Official colored.
Despite Alber's mask covering his mouth, there are so much blood its not enough to stop leaking.
For example, if it was a small mouth blood like when Jozu made Aokiji bleed, the mask would cover Aokiji's blood completely that we wouldn't see Aokiji's blood, it wouldn't leak from his mask, but Alber is bleeding so bad that the mask on his mouth isn't covering it completely.
Right before the attack, Alber is in flame-on mode.
Marco's attack power is underrated, he gave an internal damage to flame-on Alber while also fighting with Queen in 2 v 1.