When Alejandro Villanueva enrolled at West Point more than a decade ago, it became incumbent upon him to salute the American flag and stand at attention during The Star-Spangled Banner, a practice he continued once he became a commissioned officer in the U.S. Army and a member of the elite Rangers.

However after a tumultuous NFL Sunday that featured teams and players across the league reacting to President Trump's profane comments directed at those who protest during the national anthem, Villanueva felt compelled to apologize to his Pittsburgh Steelers teammates – none of whom took the field for the anthem prior to Sunday's game in Chicago – after he alone stood outside the team tunnel at Soldier Field and stood with his hand over his heart.

"This national anthem ordeal has sort of been out of control, and there's a lot of blame on myself," Villanueva, Pittsburgh's starting left tackle, said Monday.

"I made coach (Mike) Tomlin look bad, and that is my fault and my fault only. I made my teammates look bad, and that is my fault."

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Tomlin told CBS prior to kickoff that the team would not take the field for the anthem in order to remain unified despite disparate opinions on Trump and the practice of silent protest prior to NFL games.

"Whatever we do we're going to do 100%, we're going to do together," said Tomlin. "We're not going to let divisive times or divisive individuals affect our agenda."

Villanueva and his teammates indicated a day later that his presence outside the tunnel actually occurred accidentally rather than by design. He said he had wanted to see the flag before the game but was still outside when the anthem began, at which point he did not want to move. Yet he subsequently felt as if he'd broken ranks and admitted there was pressure to stand from fellow veterans, including those injured in wars abroad.

"Unfortunately, I threw (my teammates) under the bus, unintentionally," he said. "Every single time I see that picture of me standing by myself, I feel embarrassed.

"We as a team tried to figure it out. Obviously we butchered it. ... I'm not gonna pretend I have some kind of righteous voice."

However, national support of Villanueva has swelled in the past 24 hours. His No. 78 jersey has become the No. 1 seller on NFLShop.com and Fanatics.com since Sunday's game.

Villanueva said the Steelers were internally united but had decided to "stay away from the situation" given different opinions – the offensive line wanted to stand for the anthem – on how to handle Trump's remarks from a Friday rally in Alabama, when he said protesting players should be fired and were "sons of b------."

Villanueva, who was deployed to Afghanistan three times, said he has no issue with players who protest during the anthem and said several have thanked him for his service.

"I will support all my teammates, and all my teammates and all my coaches have always supported me," said Villanueva, who went undrafted in 2010, when he began serving his active duty commitment after graduating from West Point.

He joined the Steelers practice squad in 2014 and became a starter one year later.

As for his own opinions on Trump's remarks, Villanueva declined comment.

"I don't have anything to say about the commander in chief and his decisions," he said. "Nothing to comment about what the president says."

Follow Nate Davis on Twitter @ByNateDavis.

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