#4 - Brett Cecil: 4 years, $30.5 million, 2017
Miller, Holland, and now Brett Cecil end the murder's row of bad reliever contracts that the Cardinals handed out from 2017-2019. Cecil was the first of them, and somehow, easily the worst of them all.
Cecil had been a really good reliever in 3 of the last 4 seasons he pitched with the Toronto Blue Jays, so at the time, his signing seemed to be a big boost to the Cardinal bullpen. His first year was not horrible, as he threw 67.1 innings with a 3.88 ERA for the Cardinals.
2018 is when this deal went from bad to a disaster. His 6.89 ERA in 32.2 innings made him one of the worst relievers in all of baseball. Cecil tried to revamp his body heading into 2019, losing 60 pounds, but ended up developing carpel tunnel syndrome and missed the entire 2019 season before being released prior to the 2020 season.