DE Mario Williams

Vitals: The No. 1 overall pick in 2006 out of North Carolina State, he is the top defensive free agent on the market this year. He had 48 sacks in his first five seasons, the third-highest total by any player by the age of 26. Dwight Freeney and Derrick Thomas were the only two players who had more by that age. He had five sacks in five games last season with Houston before suffering a season-ending biceps injury.

Why he fits for Seattle: The Seahawks have stated a desire to improve their pass rush, and Williams isn't just one of the top pass rushers available in the open market, he's one of the top pass rushers in the game. This isn't a great pass rusher in his 30s. This is a great pass rusher in his prime. He played outside linebacker for the Texans last season, demonstrating a versatility that could give Seattle's defensive coaches a license to scheme with a roster that includes both Williams and Chris Clemons.

Why he wouldn't: He's going to be expensive. Perhaps highest-paid-defensive-player-in-history expensive. It might take $40 million in guaranteed money to add Williams. That's a ton of cash, and in Seattle, free-agent buys at defensive end have been costly. Grant Wistrom's body began to break down after Seattle signed him from St. Louis in 2004, and while Patrick Kerney had a monster season the first year after Seattle signed him in 2007, he, too, struggled with injuries his final two seasons in Seattle.