What happened: Kansas City Royals left-hander Kris Bubic is expected to begin a rehab assignment with Triple-A Omaha tonight at Werner Park. The minor-league outing is the next step in his recovery as the club prepares to bring him back to the big-league staff.

Why it matters: Getting Bubic back would give the Royals another arm as they sort out their rotation and weigh their direction ahead of the trade deadline. A healthy, effective Bubic changes the calculus on whether Kansas City sells, holds, or supplements its pitching.

What to watch: Watch Bubic's pitch count and how many rehab starts he logs in Omaha before the Royals clear him to rejoin the rotation.