T.J. Lang isn't exactly a fan of Pro Football Focus.

The Detroit Lions guard made an appearance on 97.1's Valenti Show, and said that he doesn't exactly agree with the site and its ways of grading players, especially offensive linemen.

The Detroit Lions have kicked off another season. Stay up to date with everything --take five seconds to sign up for our FREE Lions newsletter now!

In a piece by Will Burchfield of CBS Detroit, Lang's comments about PFF on the show are presented, and Detroit's guard showed plenty of fire when he spoke about the analytical site which has become popular.

“My opinion is there’s no way you can possibly accurately grade offensive linemen if you haven’t done that job before in your life. A lot of these guys, they’re not qualified to be grading NFL players,” Lang told the Valenti Show on 97.1 The Ticket. “A lot of the stuff I realize is pretty basic, obvious information. If I clearly just get whooped and let up a sack, you can say, ‘Yeah, that guy let up a sack.'” “But they don’t know anything about identification, what offensive linemen are supposed to do. They think if a guy blitzes off the edge, that’s automatically the tackle’s block, but a lot of times that’s not the case. They’ve always graded me well, which I don’t mind, but I still don’t respect it,” Lang said.

According to Lang, there are plenty of folks in the NFL who feel the same way.

“I know most of the guys that I’ve played with absolutely hate it, just because it’s started to gain so much steam now where Sunday Night Football, Thursday Night Football, they’re actually showing stats up there for the players,” said Lang. “I think it’s absolute garbage and I think most players do.”

Since its inception, PFF has only grown in popularity, but Land doesn't think there's any way those evaluators can know as much as their numbers claim, being they don't know the ins and outs of every team and their scheme.

“If a guy clearly gets beat, that’s one thing. But if you’re going to say, ‘This guy didn’t pick up the linebacker, this guy missed a blitz,’ there’s no possible way that you can know that unless you know what the offensive linemen’s responsibilities are. And nobody else knows that,” Lang said. “I don’t know what Arizona’s offensive line does. They might do something completely different than what we do. “Especially a guy sitting on the outside behind his computer looking at the game, there’s no way he knows what the hell’s going on either. It’s a total joke, in my opinion, as far as it goes grading offensive linemen.”

It's a strong and interesting take on a popular new football advancement.