1. Trevor Williams
While this may come as a suprise to many, I think Trevor Williams was the best addition by the Nats offseason. He was a perfect fit for what the Nationals needed, so signing him helped them accomplished a much needed goal this offseason. That goal was increased starting pitching depth. Williams will ease back into a starter role from the long relief role he held with the Mets and will make quality start after quality start for the Nationals, not only eating innings, but keeping the team in reach in many winnable games. His value will be unmatched compared to the rest of the guys in this ranking, boosting him to the number one spot of my list.