Former Blues and Arsenal stalwart Cech retired in the summer of 2019 and stepped straight into a board role at Chelsea when Frank Lampard was appointed manager.
But now the 38-year-old has been added to Chelsea's Premier League official squad list – purely as a precautionary move during the pandemic.
New recruit Edouard Mendy, Kepa Arrizabalaga, Willy Caballero and Jamie Cumming all sit ahead of Cech in the pecking order at Stamford Bridge.
"Petr Cech has been included in the squad as emergency goalkeeper cover," Chelsea confirmed in a statement.
"This is a precautionary step due to the unprecedented conditions currently caused by the Covid-19 crisis. He takes up a position as a non-contract player."
Cech is younger than 39-year-old Blues veteran stopper Caballero, who has himself joked previously about battling his advancing years.
Former Czech Republic goalkeeper Cech made more than 300 Chelsea appearances between 2004 and 2015, before spending another four years with Arsenal.
The 124-cap star would only be called upon by Chelsea in a major crisis, but the Blues jumped at the opportunity to register one of their most trusted lieutenants.
Ice hockey fan Cech has sustained his fitness by turning out for Guildford Phoenix, while he has also helped out in an unofficial coaching role with Chelsea's goalkeepers this season.