This is a picture of Mario Williams fixin to crush Browns quarterback Charlie Frye. Frye threw the ball away, got an intentional grounding call against him, and Williams did not get an official sack for the game.
Williams had a lot of that sort of thing happen this season. The average NFL fan judges defensive ends on sack statistics, especially someone who has been under as much scrutiny as Williams. He had 4.5 sacks, 47 tackles and 3 deflected passes.
Most of the things he did this year don't show up in stats, such as teams near the end of the season running the ball away from him.
In addition, he has been hampered for most of the season with plantar fasciitis, a painful overuse injury to the foot, but he was the only Texans defensive linemen who never missed a game this season.
I've read a lot of the descriptions of his play from various media sources, and I think the one by Pat Kirwin on NFL.com is probably the most accurate summary of his season, though it leaves out the information about his injury.
Mario Williams is a fast, strong large man, and Texans fans everywhere hope he continues to learn more technique and has a healthier 2007. Even with promising players such as Williams and DeMeco Ryans, it is hard not to look at the Texans defense as one that needs a lot more help.
Oh, and here's the aftermath picture of the Frye non-sack. Ow.