Updated project metadata. We developed and validated a workflow in S. cerevisiae combining auxin-inducible protein degradation with LC-MS/MS phosphoproteomics and used it to identify candidate phosphatase substrates during mitosis, when kinase activity is high. Our results revealed that PP2A-Rts1 influences dephosphorylation of numerous proteins in mitosis, including multiple subunits of the plasma membrane-associated eisosome complex.