Why exactly do the Padres need to "get out of James Shields's contract a few years early" as you say? It only lasts 3 more years guaranteed, so swapping him for 2 years of a lesser (albeit less expensive) pitcher in Nolasco is hardly a clear plus for them. (Shields also has an opt-out after 2016, and while it's unlikely he would exercise it at his age, it's not inconceivable if he stays durable and productive next year, especially if SD doesn't improve.) Your follow-up comment that "James Shields is one of the best starting pitchers in baseball" only confuses the issue more. Additionally, the Padres have zero room for Arcia on their MLB roster, and he's out of options next spring. I mean, the Padres might take a flier on him if he's essentially free, but you can probably leave him off this trade proposal, he's not really adding value.