LATROBE, Pa. - Alejandro Villanueva didn't play much in the preseason opener against the Detroit Lions, but he still had a long night.

"Not good, just a very sloppy performance," Villanueva assessed.

By his count, Villanueva "messed up" three of his 10 snaps.

"I just had a really bad performance," he said. "It has to be better."

It's all a part of a continuing process for Villanueva, who two preseasons ago was trying to make the transition from U.S. Army Captain and three tours of duty in Afghanistan to defensive lineman in the Eagles' camp.

The Steelers noticed him during an August visit to Philadelphia Mike Tomlin saw someone standing a head taller than his teammates on the home sideline during the national anthem and his curiosity was piqued and Villanueva eventually landed on the Steelers' practice squad as an offensive tackle.

He wound up starting 10 regular-season games and two more in the playoffs last season as the Steelers' left tackle.

But at times, Villanueva's inexperience still shows.

"I've not been playing tackle for a very long time," he said. "I've not been playing football, it's not second nature to me in a lot of cases. I tell people, I've played more soccer in my life than I've played football.

"I spend six months of the year watching film and thinking what football's going to be like. Once you actually put pads on, things are a little different and they catch you off guard."

For Villanueva, it isn't so much technique or the physical demands of the position that prove challenging on occasion.

It's simply playing the game as he's been trained to play it and as he knows he's capable of playing it without complication.

"I think most players just go out and play," Villanueva said. "I think I overthink too much sometimes in terms of, 'Where's my help coming from? Where can I not get beat?' Sometimes that gets me in trouble more than hand placement or footwork.

"It's, 'Am I ready to perform this play exactly how the coaches want me to perform it?'"

Even at 6-foot-9 and 320 pounds, Villanueva still has growing to do in a transformation that was accelerated when he took over after Kelvin Beachum was lost for the season a year ago.

"I learned a lot of lessons," Villanueva said. "The first one is, you do a lot of things in practice and you get a lot of compliments, everybody gets mistakes. But when it comes to the game on Sundays, one mistake can cost the entire game. You can play a great game and then you give up a sack, it's just really ugly.

"That's one of the things that I learned the most, the last repetition matters more than the entire rest of the game."

Villanueva has also learned the value of attacking his job with confidence.

"It's not so much the perception of what people think, how good you are," he said. "In the NFL, the result for success is how good you think you are. There's a lot of media, there's a lot of people speculating on how a player is going to perform.

"But what truly matters is how you think you're going to perform."