Russell finished sixth fastest after completing 66 laps in the afternoon session at the Circuit de Barcelona-Catalunya on Thursday.
Mercedes' 2022 car W13 hits track for first time at Silverstone
Lewis Hamilton kept tight-lipped over the saga and initially refused to confirm he would return for the 2022 season.
Lewis Hamilton, 37, was speaking for the first time since he lost the world championship in controversial circumstances to Max Verstappen.
Mercedes has won the constructors' championship for eight consecutive seasons, but Max Verstappen snatched the drivers' title in 2021.
According to the FIA's early simulations, a 2022 car would retain 86 percent of its downforce while one car length behind another.
George Russell has joined the German team from Williams ahead of the 2022 season, replacing Valtteri Bottas.
The turbo-hybrid era in F1 has almost entirely belonged to Mercedes, with the team winning eight consecutive Constructors' Championships.
F1 is gearing up for a new era with cars that include a 'ground effect' aerodynamic concept, drastically different bodywork, and 18-inch tyres.
Furthermore, the prevalence of one-year contracts had resulted in a severe lack of job security, which had begun to weigh heavily on Bottas' mind.