When it comes to the top of the Mariners rotation, the only argument that can be had is where you place the top four pitchers. According to you, the fans (at least on Twitter), the answer was overwhelmingly and resoundingly Luis Castillo, George Kirby, Logan Gilbert, and Robbie Ray. For those who didn't see it, each person won their spot in the rotation with around a 75-80% vote. However, it's that fifth spot that is a bit confusing.
What are the Mariners going to do there?
Is it going to be Marco Gonzales? The longtime bulldog that the Mariners have deployed for so long not just as a starter, but as the pitcher who was actually leading their entire rotation?
Is it going to be Chris Flexen? The KBO comeback story, who has put together a wonderful stretch with the Mariners where he started 52 games and threw 296.2 innings, averaging just over 5-2/3 innings a start before selflessly moving to the pen to help the team out?
What about Bryce Miller, Bryan Woo, Emerson Hancock, Taylor Dollard, or Prelander Berroa? Could one of the Mariners top pitching prospects join Logan Gilbert and George Kirby as recent call-ups to cement their place in the rotation?
Or could it be someone else entirely? A trade or FA, perhaps? There aren't really any pitchers left on the market, but Trader Jerry could always surprise the Mariners fan base with a move as we get into Spring Training if he sees value somewhere.
Personally, I think we see something along the lines of the following. Marco Gonzales starts as the 5th pitcher, giving them a second lefty in the rotation. Chris Flexen, despite being involved in trade rumors all offseason, remains on the team and pitches out of the bullpen. Marco gets shut down with a sore shoulder for a month or two, and Flexen steps in. He does well and is traded once Marco comes back from the IL.
To bring him back up to full health, Marco goes to the pen, and Bryce Miller gets called up. He struggles a bit and gets some time off to recoup and work with the staff. Marco comes back in, throws a stellar start, and then two not-so-great starts, and the team inserts Miller back into the rotation. With some of the MLB nervousness gone, Miller puts up a 3.57 ERA over his last 13 starts, helping to solidify the back of the Mariners rotation.
When all is said and done, It ends up being a 3-person combo to get the back end of the rotation filled out, and the Mariners end up with a good solid outing when you take the year as a whole. Pitching is one of the hardest things to predict in the game of baseball, but this is definitely a scenario that I could see happening with the last spot in the Mariners rotation.