Why do I get the feeling they will go after Greinke? Would he be a rental?
Yes, he would be a rental. Unless he completely fell in love with this town, he would be a rental.
The Nationals don't have high level prospects to trade for Grienke as anything more than a rental. I'm not even sure they have a good enough prospect to trade for him as a rental. Remember, Carlos Beltran pulled Zach Wheeler. I just don't think the Brewers are going to be interested in multiple B-/C type prospects, which is about all the Nationals have to offer right now, unless they want to part with someone on the MLB roster.