What are the Rays losing?
This one stings, Mallex was one of my favorite players to watch take the field everyday for the Rays in 2018, but I understand the move. Essentially, the Rays will lose one of their best players in 2018. They will lose the Mallex Effect on the base paths and they will lose a fan favorite.
On a separate note, they also lose the log jam that existed in the outfield.
Mallex Career 6.2 bWAR: .277 AVG/ .346 OBP/ .384 SLG/ 101 OPS+
Mallex 2018 3.5 bWAR: .296 AVG/ .376 OBP/ 40 SB/ 115 OPS+
Mallex, like Heredia will become arbitration eligible in next season and won’t become a free agent until 2023. Mallex just missed gaining Super Two Status by a few games in 2018, which would have allowed him to become a free agent a year earlier.
What this means:
The Rays lose a valuable piece of the 2018 team that won 90 games. They need to alleviate the log jam in the outfield and they did so by trading Mallex away. They lost a controllable talented outfielder who can cover some ground in the outfield and on the base paths.