KANEOHE, Hawaii -- A former NFL player deployed with 300 Kaneohe-based Marines to Iraq on Tuesday night.

Lance Cpl. Jeremy Staat was a college teammate of Pat Tillman, who also left the NFL's Phoenix Cardinals to join the Army Rangers. Tillman was killed by friendly fire in Afghanistan in 2004.

Staat tried to enlist right after 9/11, but Tillman told him to stay in the NFL. When Tillman was killed, it gave him even more motivation to join the Marines.

As the sun set, the Marines gathered their gear together and got ready to leave for Iraq.

Staat was an 11-game starter for the Pittsburgh Steelers and St. Louis Rams in 1999.

Tillman made Staat promise he would play long enough to get his NFL retirement.

"Once I had fulfilled my promise to him, he was killed. I figured I'd finish what I'd started," Staat said. "(His death) affected me because with him, Pat was always a guy you knew would come out on top. You knew in games you couldn't believe he made that block or that tackle. I expected him to come home."

Staat gave a comparison between starting in his first NFL game and deploying to Iraq.

"The first NFL game would be over in about four hours. I mean this game is going to take about seven months. The plays here are for real life or death. You make a mistake here you can't go back and play next week. So, the strain mentally is immense," Staat said.

He said he is not concerned about the lack of support for the war.

"I can't worry about the political things that are going on here, what's going on in Congress, and who's in the White House -- things like that. I've got to take care of the Marines on the left and right of me because we're going by ourselves and we have to go and protect and take care of each other," Staat said.

Staat said he had to lose more 80 pounds and get in shape to become a Marine after leaving the NFL.