All dividing cells have to accurately and efficiently duplicate all their genome to ensure genomic stability and cell viability. Considering the size of eukaryotic genomes and many replication forks ongoing at the same time, the arising question is: how are cells able to sense that DNA replication has been completed? In this study, we describe a novel checkpoint coordinating sensing of replication completion with mitosis entry. We have shown that this checkpoint relies upon translesion synthesis polymerases: Rev1 and polymerase ζ (composed of Rev3 and Rev7 proteins). By sequencing experiment, we have demonstrated that Rev7 is involved in sensing of ongoing replication and preventing premature mitosis entry. We have presented that the underlying molecular mechanism depends on the sequestration of CHAMP1, protein involved in maintenance of kinetochore-microtubule attachment, by Rev7. Our findings represent an interesting contribution to our understanding of checkpoints cell cycle control.