To be fair to Mariners GM Jerry Dipoto, he did add 4 players to the 25 man roster before August 1. Unfortunately, Cameron Maybin, Zach Duke, Adam Warren, and Sam Tuivailala have all disappointed for one reason or another.
Duke and Maybin have just been bad since donning the navy blue and teal. Tuivailala was okay before injuring his Achilles tendon, ending his 2018 and putting the start of 2019 in jeopardy. While Warren hasn’t been as terrible as most assume, he certainly hasn’t solidified the back end of the bullpen like most had hoped.