Ahead of their first game of the season, Miami Dolphins players said they would wear decals on their helmets to name Black victims of violence, and that they would stay off the field during the playing of national anthem.Credit...Joel Auerbach/Associated Press

The dissonance of playing football right now was on display on Thursday night, with excitement over the resumption of the N.F.L.’s rituals tempered in Kansas City, where Patrick Mahomes and the Chiefs were booed by a reduced-capacity crowd for standing in solidarity with the Houston Texans before the game and then cheered for clobbering them during it.

While warming up for his game against the Atlanta Falcons, the Seattle Seahawks star quarterback Russell Wilson wore a black T-shirt that said “We Want Justice” in all capital letters, along with headphones and a neck gaiter pulled over his nose and mouth as a coronavirus mask.

In a less conspicuous turnaround, Baker Mayfield said in June that he would “absolutely” join in kneeling with teammates during the playing of the national anthem this season, and he got the blessing from the Browns’ owners.

Tom Brady and Drew Brees are the two oldest active players in the N.F.L., making Sunday’s meeting the first in league history between two starting quarterbacks age 40 or older.

Cardinals quarterback Kyler Murray enters his second season with an elite wide receiver, DeAndre Hopkins, whom the team acquired in a trade in March.