Chad Greenway.
There isn't a single player that will rescue our offense this year, so I'd focus on shoring up the defense. As much as I would always love to have Bob Sanders back, I think our defensive backs are going to be at least decent this year. Our linebackers, however, appear to be our biggest defensive weakness. If we could shore up that group with a leader like Chad, I think we'd have a chance to be a top-tier defensive team. Then we'd have to pray that our offense can get its $hit together enough to score some points. Others may argue that a different linebacker would be better (e.g. Station, Angerer, etc.), and I'd understand those choices, but Chad was the first that came to mind. Maybe it's because we are contemporaries, or because he's just such a good human being, but I have a lot of respect for him both on and off the field.