Relax, you do not have to run to your computer and drop Butler, but you have to know that his value is based more on where he was drafted than on his actual performance.  Obviously, his .312 batting average is excellent (14th among big leaguers with at least 250 AB’s), but his power numbers are pedestrian for a first baseman (29 players who qualify at first have more homers than Butler’s ten), and his counting numbers are just average (50 R, 51 RBI).  

The point here is that Butler is easily replaceable, especially since he plays at one of the deepest (if not the deepest) offensive positions in the game.  So, if he is not droppable, what should you do with him?  Use his draft position value to upgrade through a trade.  You might be able to simply do a one-for-one swap of first basemen for a guy who was drafted lower but is outperforming Butler (i.e. Paul Konerko or Aubrey Huff), or you could package Butler and a number three or four fantasy starter and try to land an ace for your rotation (see how I ranked the starters for the rest of the season here.

If you can pull off a two-for-one trade, you can fill your first base slot with….

Another option to replace Butler if you need power: 

Again, you do not have to drop Heyward, but you should not be afraid to do so if there are better options available in your league.  Sure, Heyward has tons of talent, and someday, he will most likely be an elite player, but the rookie is way overvalued simply because of his name.  His eleven homers and eight steals along with a slash line of .274/.386/.459 are good (especially that .387 OBP thanks to a 13.7% walk rate), but he has been at best only a top-40 outfielder so far.  With a BABIP of .335 and a strikeout rate of 25.5%, it is hard to see Heyward improving significantly this season.  

So, like Butler, you might be able to swap Heyward straight up for a better outfielder with less name value (i.e. Angel Pagan, Andres Torres, Hunter Pence), or if you can pull off a two-for-one trade, you can fill your vacant outfield spot with…. 

Luke Scott  Baltimore Orioles  62.1% owned

Other options to fill a vacant outfield spot: 

Tyler Colvin (25.0% owned) – hitting .268 with 16 HR and a higher ISO than Scott (.280)

If you need speed, Jose Tabata (19.8% owned) – hitting .294 with ten steals since he was called up on June 9.

Other guys I would drop for Scott: B.J. Upton (98.2% owned), Adam Jones (93.1% owned), Nick Markakis (95.1%owned), Johnny Damon (87.4% owned), and Carlos Lee (89.9% owned).

So take the advice of Fleetwood Mac: