It's the most nerve-wracking time of the year for NFL coaches on the hot seat -- Black Monday -- and some guys are already without a job ... including Ron Rivera and Arthur Smith.
The Commanders made their announcement just minutes ago ... saying after four seasons with the franchise, it was time to move on from Riverboat Ron.
Rivera went 26-40-1 during his time on the sidelines ... including one playoff appearance in 2020 after winning the NFC East.