In a statement shared Wednesday on Twitter, Scherzer - a member of the MLBPA's player executive subcommittee - wrote that players have "no justification to accept a second pay cut" in order to play a truncated 2020 season.
"There's no reason to engage with MLB in any further compensation reductions," he added.
MLB and the players' union have reached a standstill in negotiations over the economics of a pandemic-shortened season. The two sides agreed to prorate player salaries for the 2020 campaign shortly after the league announced a hiatus in March, but friction has grown since then.
Players were angered earlier in May after the league proposed a 50-50 revenue split that MLBPA executive director Tony Clark compared to a salary cap. They were upset again Tuesday after the league presented a new proposal contained a sliding pay scale that would lead to severe salary cuts.
Responses were overwhelmingly negative, and other players had voiced their concerns on social media before Scherzer issued his statement.
Assuming the sides can reach a deal, the 2020 season would likely begin in early July following a resumed spring training.