MLB Trade Rumors: Why Shelby Miller for Zack Greinke Deal Would Be a Good Move

Robert KnapelCorrespondent IJuly 5, 2012

CINCINNATI, OH - JUNE 27: Zack Greinke #13 of the Milwaukee Brewers pitches in the first inning of the game against the Cincinnati Reds at Great American Ball Park on June 27, 2012 in Cincinnati, Ohio. (Photo by Joe Robbins/Getty Images)
Joe Robbins/Getty Images

There have been a number of St. Louis Cardinals trade rumors floating around over the past few days, and one thing seems to be apparent from them: The Cardinals will be looking for pitching help at the trade deadline this year.

A few elite pitchers will be on the market this summer. Cole Hamels is not officially available, though he may be very soon. The Philadelphia Phillies have begun to call teams to gauge their interest in Hamels, according to Jon Heyman of CBS Sports. Zack Greinke is another trade candidate, and Doug Mittler (Insider required) of has identified him as a possible target for the Cardinals.

Obviously Greinke will not come cheap. The Cardinals would need to give up one of their best prospects, and the Milwaukee Brewers would likely insist that Shelby Miller is included in the deal. While a deal like this may be tough for the Cardinals to agree to, it is the right move for them to make.

As good as Greinke has been this season, the Cardinals could expect him to get better if they acquire him. Throughout his career, Greinke has gotten stronger during the second half of the season, as his ERA has been 0.31 lower after the All-Star break throughout his career.

Greinke has seemingly been comfortable pitching in Busch Stadium, although his numbers come from a small sample size. He has made four appearances at the Cardinals' home stadium, and he is 2-1 with a 2.11 ERA.

There is also some reason to believe that Greinke would be open to signing an extension with the Cardinals if he were dealt to St. Louis. Ken Rosenthal of Fox Sports has noted that Greinke would likely be open to a trade to St. Louis and that an extension may be a possibility. If the Cardinals were able to trade for Greinke and then sign him to a long-term deal, they will have found their ace for the next five years.

Top Cardinals prospect Shelby Miller could find himself in the Brewers organization if the Cardinals go after Greinke. Miller has been outstanding in the past but has been terrible this year.

Miller has had a number of rough outings, and he now has the highest ERA of his career. While he is still very young, there are some concerns with Miller already.

Coming into spring training this year, the Cardinals were not happy with Miller's body composition (h/t Jenifer Langosch of They believed that it could have an impact on his durability.

Over the past 10 years, the Cardinals have had pitchers Jimmy Journell, Blake Hawksworth, Dan Haren and Anthony Reyes ranked as their best prospect in the minors by Baseball America. While Miller has more talent than everyone but Haren, the other three pitchers should serve as cautionary tales for the Cardinals.

There is always a risk with pitching prospects, and it is almost always better to trade an uncertainty for a highly valued commodity.

Even with these concern, Miller is still an incredibly talented pitcher with a world of potential. Trading him is not something that should be taken lightly.

Miller has the potential to be a future ace for the Cardinals, but they are a team that is in a position to get back to the World Series now. Greinke could help lead the Cardinals to their second straight title, and that would make dealing Miller worth it.