As I just said in another thread, Johnson is a lot like Porcello in some ways -- not many strikeouts, lots of ground balls, doesn't walk guys. Two big differences, however, are that Porcello can start, and that he's a whole lot younger with a significant chance to improve. Plus Porcello is much more effective his first time through the order than he is later in the game. So Porcello might be just as good out of the bullpen as Johnson, plus could be used to spot-start or to replace an injured guy in the rotation.
Also, after his 50-save season, the arbitration-eligible Johnson might get a ridiculous raise.
So I wouldn't make that trade.
Edited Jan-15 by six-hopper