SPARTANBURG, S.C. – Amini Silatolu is usually a man of few words, an offensive lineman who has let his play do the talking.

This season, he's hoping to break the silence.

The Panthers' second-round draft choice in 2012, Silatolu started 15 games at left guard as a rookie but has totaled 13 starts over the past four seasons. He sat out the 2016 regular season entirely but is now back with the Panthers and is making a good second impression at training camp.

"It's like I never left," Silatolu said. "Work and win. Help any way I can – guard or tackle."

Lately, it's been tackle. Silatolu was a dominant force at offensive tackle at Division II Midwestern State but hasn't played the position in the NFL, though he did prepare for that possibility in both 2014 and 2015 before injuries derailed him. But with the Panthers being cautious with starting left tackle Matt Kalil so far, Silatolu has taken tons of first-team reps there and has more than held his own.

"Amini is having a really solid camp," head coach Ron Rivera said. "I feel good about the guys that we have.

"There is a lot more depth. It was something we had purposely gone out and done. We wanted to make sure we had the kind of depth we have right now."

There was a time where Silatolu appeared to be on the fast track to being a longtime starter in the league as opposed to a valuable provider of depth. After showing a lot of promise playing and starting right away as a rookie, he held the same role in 2013 before suffering a torn right anterior cruciate ligament four games in.

Various injuries cost him nine games in 2014, and in 2015 – as a reserve after guards Andrew Norwell and Trai Turner had established themselves – he tore his left ACL after playing in nine games.

Silatolu became an unrestricted free agent after the 2015 season. The Bears brought him in just before training camp last year but waived him before the first game. He spent the 2016 regular season getting stronger – physically and mentally.

"I was still healing up from the previous ACL in 2015, so I just sat out the year," Silatolu said. "It helped me a lot. My body is fully recovered. I feel good this year.

"My mind never left the game. I was still watching, still studying – watching a lot of Panthers games. My plan was that if I had the opportunity, this would be my first place to come to."

Silatolu said he weighed about 325 pounds this time last year, but with his focus last fall on running to rehab his knee, he got down to 285. He's now at 308 pounds – heavy enough to compete at guard and tackle but also light enough to do what is required of a tackle.

"You're working with quicker guys out in space," Silatolu said. "Being in better shape is helping."

Defensive end Wes Horton tangled with Silatolu his first time around with the Panthers. Horton has lined up some at defensive tackle this year at training camp, so the second time around he's faced Silatolu at both guard and tackle.

"He seems like a very determined player right now," Horton said. "I see a really fine focus with him. He has a lot to prove, being off a year and coming back. When you look in his eyes at the line, he looks very serious, very focused.

"He used to be a starter in this league. The only thing that's really held him back has been injuries. I just think he's real determined to get back to where he was."

It is, per usual, a quiet determination.