Week three was an eventful one for the NFL. On Friday, President Donald Trump called NFL players who protest police brutality by sitting during the national anthem “sons of bitches” who should be fired. This resulted in dozens of players taking a knee during the pre-game ceremonies in days following.

Starting Pittsburgh Steelers left tackle Alejandro Villanueva received a lot of attention for standing in the tunnel with his hand over his heart during the anthem while his teammates stayed in the locker room.

Villanueva is a former Army Ranger who earned a Bronze Star medal and served three tours in Afghanistan. After his service, he joined the Philadelphia Eagles and then the Steelers in 2014.

Many fans responded positively to his gesture by purchasing his jersey, a rarity for an offensive lineman. Fanatics, the company that runs the NFL’s online store, said that Villanueva’s jersey was the most popular sold between Sunday and Monday. Even though he’s received some positive responses for his decision, Villanueva issued an apology on Monday.

To avoid any on-field controversy, Steelers head coach Mike Tomlin asked his team to remain in the locker room during the national anthem on Sunday. “I was looking for 100 percent participation,” Tomlin said in a post-game press conference. “We were gonna be respectful of our football team.” Villanueva wasn’t bothered by kneeling teammates and said many have of those who did have expressed gratitude for his military service.