Breaking up is always hard to do, but in baseball, well, that's business.

When the St. Louis Cardinals and Atlanta Braves begin a three-game series tonight at Busch Stadium, there will surely be some emotions being held in check by Braves starter Shelby Miller and Cardinals outfielder Jason Heyward. Of course, these two were in the opposite clubhouses prior to an offseason trade.

Miller (5-6) will start against his old team on Saturday. Despite a losing record, Miller has been outstanding, boasting a 2.33 ERA. If he still played for the Cardinals, it's not outrageous to think he would have posted double-digit wins by now.

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Heyward continues to be a polarizing player, one with great skills, but seemingly can't put it all together. Once considered a potential sure-fire star, the debates that raged in Atlanta over Heyward's production, now spills into St. Louis debates.

Entering Friday's games, Heyward is batting .284 with nine home runs and 33 RBI.

If judging trades, it's hard not to say the Braves got the better end of this one. It's getting late to think that Heyward will blossom into the player many believed he would become.