With that being said, after the latest Owens start, there has to be some thought for trying Barnes as a starter 5 days from now.
The way off-days line up, there are only two necessary #5 starts remaining until 5/28, when Rodriguez should be ready to return with a good amount of AAA tuning-up.
Not to say I want to see more of Owens, but perhaps Johnson or Elias could start those two games. Neither of them look particularly ready-for-primetime just at the moment, either; but that fact doesn't mean there's a compelling reason to jerk Barnes around again, when he's actually seeming to take to the role he's been given. Heck, even Cuevas would be hard-pressed to throw as ineffectively as Owens has (although he might not be so lucky!).
But they still have 8 guys in the bullpen and that can't last. And EdRo and Kelly are on the way back. 2 or 3 guys are gonna have to go from this pitching staff.
Rodriguez will get the #5 starter spot whenever his knee's 100% and his arm strength is back. Owens, Johnson, Elias, Cuevas...the placeholder doesn't matter. Kelly would almost 100% certainly pass through waivers right now -- his salary's in the millions, he's got only 2 years control remaining after 2016, he's on the DL with a shoulder-related injury, and he "performed" to an ERA over 9 -- so the Sox could probably park him in Pawtucket if there's no ready opening when his rehab's done, if need be.
But I agree that having all three of Hembree, Barnes, and Ross in the bullpen at the same time is completely redundant. Almost as redundant as Tommy Layne (23 batters faced in 28 games...really?).
Still, if Farrell prefers the 3-man bench and 8-man pen in a stretch where the Sox play 16 games in a row, who are we to question the manager's decision?