12:45 PM PT -- Colin Kaepernick has expressed support for Stills and Wilson, tweeting "My Brothers @kstills and @ithinkisee12 continue to show their unwavering strength by fighting for the oppressed! They have not backed down, even when attacked and intimidated. Their courage will move the world forward! 'Love is at the root of our resistance!'"

Not a ton of players took a knee in protest during the NFL's fist week of regular season games ... but the first to do so were from The Miami Dolphins.

Miami wide receivers Kenny Stills and Albert Wilson quietly took a knee during the anthem of Sunday's contest against the Tennessee Titans. Their teammate, Robert Quinn raised a fist during the song.

You'll remember ... prior to the season, NFL owners approved a rule that required players to either stand or wait in the locker room while the anthem was played. The rule was put on hold after significant backlash from the players.

Both Still and Wilson also took a knee during the preseason and stated they'd continue to do so during the regular season.

President Trump took a shot at the NFL and player protests before Sunday's games, saying, "Wow, NFL first game ratings are way down over an already really bad last year comparison. Viewership declined 13%, the lowest in over a decade. If the players stood proudly for our Flag and Anthem, and it is all shown on broadcast, maybe ratings could come back? Otherwise worse!"

As we reported -- Nike named Colin Kaepernick the face of the "Just Do It" campaign's 30th anniversary -- a move hit with a ton of praise and controversy too.