For a large portion of the 2018 season the Cincinnati Reds carried eight relievers. While I absolutely hated it, I completely understood it. The Reds starting rotation was lucky to finish the sixth inning. Pitch counts often were creeping towards 100 pitches by the end of the fifth inning. The rotation itself, outside of Castillo and Harvey, seemed to be in constant flux due to injuries and poor performances.
On paper, the 2019 Cincinnnati Reds rotation appears to be about as middle of the road as you can get. Castillo, Sonny Gray, Tanner Roark, Disco, Alex Wood and now Tyler Mahle are all at least middle of the rotation guys . They will eat innings for your team if nothing else. I am expecting these guys to put up 6 innings nearly every appearance. Hopefully they will add plenty of quality starts, to boot. Why would you need eight relievers to back them up?
Madison Bumgarner said it best when referring to the idea of a bullpen opener, "If you're using an opener in my game, I'm walking right out of the ballpark." I think it's an insult to starting pitchers for their goal to be complete 5 innings and hand the rest off to the bullpen. This leads me to believe there will be one bullpen pitcher that is extremely under utilized when he could be getting innings in the minors.
Meanwhile, the Reds are showing more roster depth on the bench than we have ever seen in the past 20 years. Rather than opting to have a fifth bench player, with a solid bat, you would rather use that position for an excessive amount of relievers. Matt Kemp, Scott Schebler, Jose Iglesias, Derek Dietrich, Phillip Ervin and Nick Senzel are all bats that could be getting significant playing time in the majors. All of which will have a significant impact on scoring runs and winning games for this team. It makes zero sense to me how you can justify using that roster spot for a player who will, maybe, pitch one or two innings a week at most. I think it also shows little faith in a rejuvenated rotation. While I don't believe or expect this rotation to be as good as the 2012 Reds. I do expect them not to be warming up the bullpen in the fifth inning nearly every night.