These offseason additions led to titles https://www.mlb.com/news/world-series-winners-biggest-offseason-moves Every champion can point to an important move, whether it’s a blockbuster trade, a splashy free-agent signing or an under-the-radar pickup whose full impact is only revealed months later. Here is a look back at the biggest addition made by each of the past 31 World Series winners, since the #MLB