We have nobody to replace him with. John Danks may not win you a game all by his lonesome, but he's been giving QS and with the new bullpen 3 ER in 6 IP is just fine thank you. If they want to get Rodon a couple starts, seeing how that goes, then shipping Danks I'm more receptive.
Danks would do well for himself in the NL, not a world beater but a decent guy to have in the rotation. You dont just leap at the first buyer, see if a market can develop for a guy that wont cost much to get but could be decent.