Yesterday John Mozeliak was asked about the Cardinals plan for Jhonny Peralta’s expected Tuesday return to the team and he said, in short, that Diaz would stay put, Matt Carpenter would move to second, and Peralta would play third.

If Peralta can return to his 2013-2015 form, then with him will come an average fielder, a .270 hitter, with some pop in his bat, and many years of experience at the big league level.

With his return the Cards are in an interesting scenario with Kolten Wong. We all know Wong signed a 5 year, $25 million deal during spring training, but with the emergence of Diaz, the flexibility of the Cardinals infield, and Wong’s .225 average and 5 RBIs on the year (both worse than Adam Wainwright) Mozeliak and the Cardinals management are in a tough position. It doesn’t seem likely that Wong will get optioned to Triple A upon Peralta’s return (we expect it to be Hazelbaker), but at some point soon something is going to have to budge.

And things get even trickier. Diaz is a fan favorite, there is no question about it. He started off the season among the best in baseball, and don’t hate me for saying it, but I’m slightly worried about him moving forward. Over the first month of the season he hit .398, but over the past two weeks he has hit .196 in 59 at-bats, and in the past 30 days Wong (.308 OBP) is getting on base more frequently than Diaz ( .296 OBP). Diaz could definitely just be going through a dry spell and soon pick up where he left off, but he could also continue going downhill, like Hazelbaker is seeming to do after his hot start and pitchers around the league are figuring him out.

But the uncertainty with Wong and Diaz, and anyone else for that matter, will work itself out. Here’s my prediction: Peralta will come back, Wong will get fewer at-bats and the Cards will see how things are going with Carp, Diaz and Peralta in the infield joined by Adams. If the infield is thriving and playing Wong on a given day is seeming to be more and more of a liability, I bet he’ll get sent down to AAA to get more at-bats while the Cardinals figure out whether it’s worth keeping or trading him.

On the other hand, if any of the four infielders start going downhill, it will be open season. If Adams starts struggling, Moss will be vying for first. But Carp could also play first and a spot for Wong could open up, or Holliday could come to first and Hazelbaker/Pham could jump into the outfield. We could go through the diamond, and in each position a struggling player could be replaced by the best candidate off of the bench, without positions considered because of the roster flexibility.

This flexibility is great because what it means is that we are going to have survival of the fittest. Rosters will be very carefully handpicked and can be constantly changing based on who is hot. If anyone in the infield struggles enough, there will be Gyorko, Wong and Moss (and maybe even Garcia), to try and replace them. Is it great for the individual players? Depends on the person because it will be a very competitive and high pressure environment to get playing time, but for the team (as long as chemistry stays intact) it will be positive, and for us fans, it’ll be fun to watch.

Photo credit Dennis Wierzbicki-USA TODAY Sports