ORLANDO – Titans head coach Mike Vrabel knows what he's looking for from his offensive line.

Knowing exactly which guys will line up in front of quarterback Marcus Mariota in the season opener, however, remains to be seen.

Here at the NFL owners meetings on Tuesday, Vrabel said new offensive lineman Kevin Pamphile is a contender. Later in the day, the Titans agreed to terms with former Texans lineman Xavier Su'a-Filo.

"I want them to protect our quarterback," Vrabel said of the team's offensive line. "I want them to play together as a unit. When people watch them play, (I want them to) talk about them playing better as a unit than maybe they do individually. I think it is hard for offensive linemen to get a lot of recognition. But I do know when those guys are playing as a unit and they are smoking it off the ball, and they are playing physical, and they are protecting the quarterback, good things can happen."

The Titans signed Pamphile, who spent the last four seasons in Tampa Bay, to compete. The Titans like Pamphile's versatility. He's played guard and tackle in his career, and is capable of playing every position on the offensive line.

In his career, Pamphile (6-5, 310) has played in 53 games with 33 starts, including 15 starts at left guard last season for the Buccaneers. Pamphile, who played collegiately at Purdue, started 14 games for the Buccaneers in 2016.

Su'a-Filo, who played collegiately at UCLA, started 31 of the past 32 games over the past two seasons for the Texans. Su'a-Filo (6-4, 310) started all 16 games for the Texans in 2017. He's played in 56 games in his NFL career, with 41 starts

"Met with Kevin and enjoyed our conversation, and our meeting," Vrabel said of Pamphile early in the day, before the team reached a deal with Su'a-Filo. "We felt he was a guy who has had some playing experience and has started games in the National Football League. The thing I talked to Kevin (about) is there is an opportunity. There is an opportunity at his position.

"If he was a left tackle, I'd say: You're probably not going to start for us, Kevin. But he has a chance to start for us, like a lot of other guys at that position."

So where will Pamphile compete?

The Titans recently signed right guard Josh Kline to a contract extension, and made a tender offer to Quinton Spain, a restricted free agent who has been a starter at left guard the past two seasons. Center/guard Corey Levin, a sixth-round pick by the Titans last season, remains under contract behind starting center Ben Jones. Brian Schwenke, a reserve last season, is a free agent.

Taylor Lewan is the team's starting left tackle, and Jack Conklin is the team's starting right tackle, although he's currently recovering from a knee injury. Dennis Kelly is the team's top reserve at the tackle position.

"We like his versatility inside," Vrabel said of Pamphile. "He is going to provide competition to the guard spots, and certainly center. He can snap the ball. Any time you are versatile, it gives you a chance. …  Kevin is one of those guys who can maybe do more than one job. So when you get down to it and you are building a roster, you are like, OK, this guy can do two jobs, this guy can do one, this guy can do three. We need the guy who can do three because you have only so many roster spots, especially come Sunday."

Vrabel said the Titans are always "looking to add good players" on the offensive line, indicating more competition could be added either in free agency or the NFL Draft. He said young offensive linemen sometimes need additional time to develop.

Vrabel is high on Lewan, a two-time Pro Bowler who has started 53 games over the past two seasons.

"Taylor has a great personality. He has a great work ethic. He is driven. He is driven to be one of the great players at that position, and he has the ability to do that," Vrabel said. "But like all players and all coaches, we can improve on what we did last year."