Saturday roster moves raise 3 big questions for KC Royals

Why did the KC Royals choose to bring back Brad Keller this season?

Good question. Keller hasn't thrown a big league pitch since May, when right shoulder impingement syndrome forced him onto the IL. The two-time club Pitcher of the Year was 3-4 with a 4.29 ERA at the time, but had walked 40 batters in 43.1 innings and surrendered 11 runs over his last 13 frames.

Keller also struggled on subsequent minor league rehabilitation assignments, going 3-4, 10.24 across stops in the Arizona Complex League and at Double-A Northwest Arkansas and Triple-A Omaha. But he pitched two scoreless innings in each of his most recent outings (Sept. 1 and 4).

Keller's return means any concerns (if any) the Royals have about his shoulder must be minimal, which helps explain why he's back with the club. He'll pitch sooner or later — he wouldn't be on the 28-man roster unless the club plans to use him. And because he'll be a free agent for the first time after the World Series ends (unless KC chooses to re-sign him before then, which seems extremely unlikely), the front office probably wants to see how he'll fare against major league bats before deciding whether to pursue him over the winter.

And the final question...