Left tackle Tyron Smith has been an anchor on the Cowboys' offensive lineman since his rookie season.

And his performance hasn't gone unnoticed. The Cowboys rewarded the former USC star and first-round draft pick with a long-term contract.

Now, Pro Football Focus has rated Smith as the NFL's second-best offensive lineman, behind only Cleveland Browns left tackle Joe Thomas.

Here's what PFF had to way about Smith: As he did for our All-Pro team, Tyron Smith comes in right behind Thomas when it comes time to hand out another honor. Evaluating the two beasts was closer than you'd imagine, with Smith's exceptional run blocking (96.8, best among offensive tackles) hard to overlook, but it was Thomas' superior pass protection that gave the veteran the upper hand. Smith didn't have a single game graded below -1.0 (0.0 is average) as a run blocker all season, and while he allowed two fewer pressures than Thomas, he also pass-protected for 124 fewer snaps. On a per snap basis, Thomas' edge as a pass protector is as comfortable as Smith's is as a run blocker. After a tough first year at left tackle in 2012, Smith has now established himself as one of the league's elite blockers.

Smith was also first runner-up for PPF's Best Run Blocker.

The Dallas offensive line is arguably the best run blocking group in the league, and they are led by LT Tyron Smith. In what was a career year for the 25-year-old, Smith had the second-most positive graded run blocks among tackles. In addition, he earned negative run block grades on just 7.9% of run plays, second-lowest among all players.

Cowboys linebacker Sean Lee was the fourth runner-up in for PFF's Comeback Player of the Year.

Prior to the 2015 season, Sean Lee had appeared in just one of the last 24 competitive matches for the Cowboys, including missing the entire of the 2014 season. He showed few signs of rust however, getting 2015 off to a bang with a nine defensive stop performance against the Eagles in Week 2. Lee's 92.3 overall rating ranks third among linebackers.

Cowboys rookie defensive back Byron Jones was PFF's second runner-up for Defensive Rookie of the Year.

Dallas' first-round draft pick showed his versatility in 2015, spending time at outside cornerback, in the slot, and at safety in the first year of his career. He was solid against the run, but it was his play in coverage that earned him a spot as a top-three defensive rookie, where he notched six pass breakups over the course of the year. The Cowboys had the foresight to uncover his versatility, and by the end of the season, Jones had played 249 snaps as an outside corner, 185 as a slot corner, 270 as a free safety, and 186 as a strong safety or extra linebacker in the box. With front offices now salivating for that chess piece player who can move all across the defensive backfield, Jones thrived in his varying role in the Cowboys' defensive backfield.

Cowboys right guard Zack Martin was fourth runner-up for Best Pass Protector.

Martin was our highest-graded pass blocking guard, at 90.7. He allowed just one sack all season and finished with a second-best pass blocking efficiency of 98.3.