Sometimes, offseason acquisitions work out. Sometimes they don't. Sometimes, they are spectacular failures.
Kevin Mitchell was brought in to the Red Sox roster in 1996. At this time, the Red Sox were getting a lot of criticism for employing an individual known for his involvement with the formation of rotisserie baseball. One of the effects of his involvement was a lot of big-time hitters at every position, such as Wil Cordero, Jose Canseco, Mike Stanley, and more. The 1989 NL MVP had big power.
Kevin Mitchell played 1995 in Japan and came back to the states to play right field and designated hitter for the Red Sox. He only played in 27 games for the Red Sox though and did not show close to the kind of power that was expected from him. Mitchell hit only two home runs, but he did hit .304/.385/.413/.798, so it was not a total loss. However, Boston expected more. Mitchell was making a reasonably high salary and the Red Sox were not going anywhere, so he was shipped off to the Reds for Roberto Mejia and Brad Tweedlie, neither of whom ever made the Majors in Boston.