Nationals' third baseman Ryan Zimmerman has been out of action since late July after he tore his hamstring, and Cardinals' pitcher Michael Wacha recently return to action after missing over two months with a stress reaction in his shoulder. How will these two be utilized in the postseason?

Zimmerman has missed the last 50-plus games because of his injury, but he began playing in rehab assignments on Tuesday. In his first [simulated] game, he played three innings at first base and went 2-for-5 with two doubles. He also ran the bases comfortably and reported no discomfort in his hamstring. He then played five innings of defense in a simulated game on Wednesday, with three of them being at first base and two of them at third. He's schedule to DH on Thursday and play seven innings of left field on Friday, so it looks like the Nats are looking to have him prepare for a number of roles.

Adam Kilgore of the Washington Post believes that Zimmerman could be used at first base and in left field to give Adam LaRoche and Bryce Harper days off when the team is facing a tough lefty pitcher. As for Zimmerman returning to his usual third base position, Williams might be hesitant putting him back there immediately. Anthony Rendon has been having an excellent season (.285 AVG with 20 home runs and 80 RBIs) and he's been playing third during Zimmerman's absence. Williams could move Rendon to second (where he's played a total of 110 games in the past two seasons) and bench Asdrubal Cabrera, but it's unknown if he wants to do that much tinkering with the lineup. After all, Zimmerman has missed an extensive period of time and it's no guarantee that he comes back at full force.

There's a similar dilemma in St. Louis, where the Cardinals and manager Mike Matheny have a tough decision to make in terms of the starting rotation for the postseason. Coming into the 2014 season, Michael Wacha was supposed to be the No. 2 pitcher behind ace Adam Wainwright, but a stress reaction kept him out of action from June until September. He struggled in his first two starts back from the DL (seven innings pitched with a 7.72 ERA and 1.86 WHIP), which could lead to speculation that he'll be in the bullpen during the postseason, especially since the team skipped his start on Sunday.

Instead, Wacha threw a 30-pitch bullpen session to address his command and the team also made sure his shoulder was doing fine. The Cardinals have cleared him to return to the starting rotation on Saturday against the Cincinnati Reds after speculation that he might not pitch for the remainder of the regular season, but it's still a possibility that they'll use him out of the bullpen during the playoffs. Such a move would be less demanding on his recently recovered shoulder injury and they have a solid rotation that includes Wainwright, Lance Lynn, John Lackey and Shelby Miller that can likely get them through even the toughest of series.

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