It was during the first half that an activist ran onto the field before he was eventually taken care of by away team Los Angeles Rams Bobby Wagner and Takkarist McKinley.
- He looked like he wouldn't be on the field.
I saw the safety guy was having a little trouble so I helped out," Los Angeles Rams linebacker Bobby Wagner said, according to CNN.
Afterwards, the animal rights organization Direct Action Everywhere took on the incident.
Monday's game in San Francisco, California ended 24-9 to San Francisco who now have two wins and two losses so far this season.
The reigning champion Los Angeles Rams are also 2-2 in games.
See the situation in the player above.