The Dumbest Trade of All-Time

Jason Varitek a.k.a. "The Captain"

If there is one trade in the entire history of Major League Baseball that demonstrates a “selling” team capitalizing on a “buying” team’s mistake, it's this one.
At the trade deadline of the 1997, the Seattle Mariners stood at 60-47, leading the American League West by just a half-game with a team built to be a contender down the stretch. On the other hand, the Boston Red Sox’s playoff aspirations had disintegrated as the team was 17 and a half games out of first place in the AL East. To bolster its bullpen, Seattle sent minor league catcher Jason Varitek and minor league pitcher Derek Lowe to the Red Sox in exchange for expensive reliever Heathcliff Slocumb.
The Mariners indeed made it to the playoffs in ’97, but Slocumb had little to do with it. In his first month with the team, Slocumb went 0-3 with a 5.63 ERA out of the ‘pen. In his only appearance in the postseason, he saw two innings on the mound in which he surrendered one run on three hits. Seattle was knocked out of the American League Divisional Series by the Baltimore Orioles and a season later Slocumb departed for free agency & went to Minnesota to finish up his career.
Varitek would spend his entire big league career in a Red Sox uniform and would serve as Team Captain for several of those seasons. He played on two World Series champion teams and was a three-time All-Star who was a serious contender for the AL MVP Award in 2005.
Lowe, also an All-Star on multiple occasions, serviced Boston well with a 100-inning season in relief, a 42-save season and a 21-win campaign.