Seems like the problem is not the using of his sinker. He is using it but, he has lost command.
Porcello, dressed in funereal black while standing in front of his locker, dismissed the suggestion that he was "lost” on the mound.
"No, I don't feel lost," he said. "I know what's going on. A lot of fat pitches. Bottom line is executing. That's it."
While it was a huge mistake, first off trading him and then giving him that extension, It is not Farrell's or Ben's fault regarding his execution. This is on him and at least he is aware of it. Shut him down till the all-star game and work with him whatever he has to work. it's enough already.