OXNARD, Calif. -- When the Dallas Cowboys selected Tyron Smith in the first round of the 2011 draft, it was the beginning of a change in philosophy.

Never before in Jerry Jones' tenure as the team’s owner and general manager had the Cowboys chosen an offensive lineman in the first round. It always seemed strange how Jones looked to build his offensive line, considering he played the position on a national championship team at Arkansas and should know the importance of the position.

Since taking Smith, the Cowboys picked Travis Frederick in the first round of the 2013 draft. Last May, they took Zack Martin – not Johnny Manziel – with the 16th pick of the first round.

The Cowboys have rebuilt an offensive line that grew old together into one that could be the envy of the NFL.

“We really feel in a lot of ways the offensive line is the heartbeat of the football team,” coach Jason Garrett said. “If you look back at some of the great teams in the history of this league and the history of this franchise, there were always great offensive linemen and great offensive line units. When you have those guys, you can be physical. You need to be physical, particularly in our division, particularly at the end of ballgames, particularly at the end of the season, and that can really positively impact the rest of your team. The quarterback will play better, the receivers will play better, obviously the runner will play better and the defense will play better when you’re good on the offensive line. We’ve made a very conscious effort as a franchise and organization to do that, and we feel like we’re starting to see that group really develop and become the strength of this football team.”

Smith is the centerpiece of that rebuilding job. He has started all but one game since arriving, and he moved from right tackle to left tackle at the start of the 2012 season. He played right tackle at USC and needed some time to adjust to the left, but last season he was named to the first of what should be many Pro Bowls. He was a second-team All-Pro pick.

The $110 million total of the 10-year deal is the highest the Cowboys have given to a non-quarterback in franchise history. According to sources, Smith received a $10 million signing bonus as part of the eight-year extension totaling $97.6 million, and he is guaranteed $40 million.

The best part of the deal for the Cowboys is Smith's age. As he begins his fourth season, Smith does not turn 24 until December and is now signed through 2023. Garrett said it sometimes is difficult to remember Smith is so young.

“Look at him when he walks into the room,” he said. “And beyond that, beyond just his physical stature, he’s got a real maturity about him. It’s really impressive and a lot of the guys have to deal with a lot of things when they transition from college football to pro football. He’s something else. And the kind of guy he is. We really emphasize the importance of mental toughness. We believe that’s a distinguishing trait in players and in teams. And he represents that in spades. He’s off the charts. We love him to death.”