This trade wasn’t franchise-altering, but it was still a bad trade where the Red Sox got the completely wrong end of the deal. Travis Shaw was a Red Sox draft pick who worked his way through the minors and made his major league debut in 2015. In 2016 he beat out the Red Sox big (literally and figuratively) free agent signing Pablo Sandoval for the starting third baseman spot coming out of camp in 2016.
Shaw was a solid fielder who showed promising power at the plate and ended up hitting .251 with 29 home runs and 107 RBI in his two seasons with Boston. However, in the winter of 2016 then-President of Baseball Ops Dave Dombrowski traded Shaw to Milwaukee for reliever Tyler Thornburg. It was a curious move since, even though he’d pitched well for the Brewers, Thornburg came to Boston injured.
Thornburg started the 2017 season on the IL with a shoulder injury and was then diagnosed with thoracic outlet syndrome which caused him to miss the entire season. He finally made his Red Sox debut in July 2018 but was ineffective and inconsistent. For some reason (most likely to save face on the trade), they re-signed him to a one-year extension in 2019.
Thornburg was even worse in 2019, becoming known among Red Sox fans as “Alex Cora’s white flag” since he was only ever put into games when the Red Sox were losing by a lot. He was demoted to the minor leagues in June and released by the team in July.
Meanwhile, Shaw hit 31 home runs for the Brewers in 2017 and 32 in 2018 as he helped them come to within a hair’s breadth of the World Series in 2018.
As was stated above, this wasn’t a trade that hurt the Red Sox too much, but it is one that they completely and utterly lost.