In the third quarter, Freeman and Donald each were flagged for unnecessary roughness after the skirmish. Freeman appeared to pull at Donald's helmet and threw a punch after the two shoved each other.
Falcons defensive end Takk McKinley also was penalized for unnecessary roughness for his involvement in the fight.
The scrum came after an interception thrown by Matt Ryan. The ball tipped off the hands of wideout Mohamed Sanu and was picked off by Rams linebacker Cory Littleton. Los Angeles held a 20-3 lead at the time.
Third-string tailback Brian Hill replaced Freeman in the lineup. Backup running back Ito Smith was previously ruled out with a head and neck injury earlier in the matchup.
Freeman had seven carries for 19 yards and two receptions for six yards before being disqualified from the game.