Anthony Veneziano
The Royals called up reliever Anthony Veneziano for the first time in his career in mid-September, he pitched 2 1/3 innings in two games against Detroit, and didn't appear again for the rest of the season. He's remained on the Royals 40-man roster ever since, but it's likely that he'll be one of the first to go when the Royals need to clear spots. His brief appearance in the major leagues was likely a toe-dip, and the team will probably give him more of the same opportunities in the future. For now, with a veteran reliever like Chris Stratton incoming, a rookie like Veneziano is most vulnerable to get the bump.
His two major leagues innings are hardly an accurate picture of what he'll look like with more under his belt, but his performance in Triple-A this year doesn't entirely speak in his favor. He pitched 89 2/3 innings in Omaha for a 4.22 ERA after throwing 42 1/3 innings for a 2.13 ERA in Double-A. Clearly, he needs more time and development in the minors before he'll get more major league innings.
Jonathan Bowlan
Reliever Jonathan Bowlan is in a very similar boat to Veneziano; he pitched three innings this season, two against Detroit as an opener, and one against the Yankees in September, and the Royals have yet to send him back to the minors. In his start against Detroit, he gave up three hits, including one home run to Miguel Cabrera in what would go on to be a blowout in the Tigers' favor. During his one inning against New York, he gave up two hits but no earned runs.
Bowlan's minor league picture is a little dicey; he spent a little over two years in rookie/A-ball, moved quickly through Double-A despite pitching for a 7.06 ERA over 74 innings there. In Triple-A, he pitched only 67 innings for a 5.24 ERA before getting called up to the major league team, so he seems like an easy candidate to send back down to the minors.