Jon Gruden pinpoints several spots where Jordy Nelson's 'it' factor will help Raiders

Jon Gruden has made several notable changes to the Raiders roster. But none have been bigger than swapping out Michael Crabtree for Jordy Nelson. Recently, he explained what drew him to the former Packers wideout.The Raiders have signed or re-signed 22 free agents since mid-March. Jordy Nelson remains that school's biggest fish.

The former Green Bay Packers receiver inked a two-year, $15 million deal with $13 million guaranteed. He's the most recognizable on the massive signings list, and prompted the release of Michael Crabtree, a popular and productive, yet mercurial talent who signed with Baltimore.

It doesn't matter that Nelson's nearly 33, coming off a disappointing statistical season by…