There's been some discussion at the back end of the Sale trade thread about the back end of our rotation, and whether thinking it's a problem makes you a horse's back end. I figured I'd dig into it since it wasn't really a trade-specific issue.
Maybe looking at the teams who ended up with a >120 ERA+ the last decade or so would be instructive:
2016 CHC, 128, #s 1-5 all made 29+ starts (!), 6th starter got 5 GS / 38.1 IP
2016 CLE, 122, # 4&5 each made 25 GS, 6th starter got 9 GS / 60.2 IP, 7th starter got 10 GS / 53 IP
2016 WSN, 119, 5th starter made 19 starts, other guys got 6 GS / 44 IP (Lopez), 8 GS / 38.1 IP, and 4 GS / 21.1 IP (Giolito)
2015 STL, 134, #s 1-4 all made 30+ starts, 6th starter got 8 GS / 60 IP, 7th got 6 GS / 31.1 IP, Adam Wainwright got 4 GS / 28 IP
2015 PIT, 121, 6th starter got 11 GS / 63.1 IP, swingman got 8 GS / 71.2 IP
2014 WSN, 124, only fielded 18 pitchers all year (!), 6th starter got 5 GS / 25.2 IP, swingman got 7 GS / 50.2 IP
2013 KCR, 120, 5th starter got 15 GS / 94 IP, swingman Bruce Chen got 15 GS / 121 IP, two prospects got 5 GS (Duffy) and 3 GS (Ventura)
2012 CIN, 123, #s 1-5 all made 30+ starts, 161 between them, damndest thing I ever saw
2012 TBR, 121, #s 1-4 all made 31+ starts, 6th starter got 8 GS / 38 IP, 23yo Chris Archer got 4 GS / 29.1 IP
2011 PHI, 127, Halladay/Lee/Hamels/Oswalt, swingman got 15 GS / 114.2 IP, 7th starter (Joe Blanton) got 8 GS / 41.1 IP
2009 SFG, 120, 5th starter (45yo Big Unit) got 17 GS / 96 IP, 6th starter (Brad Penny) got 6 GS / 41.2 IP, 7th starter 5/30, 8th starter 6/28
2008 TOR, 122, 5th starter got 19 GS / 111 IP, 6th starter got 12 GS / 65 IP, 7th starter 6 GS / 42.1 IP, 8th starter 5 GS / 27 IP
2007 BOS, 123, 6th starter (Lester) 11 GS / 63 IP, 7th (Gabbard) 7 GS / 41 IP including a CGSO, 8th (Buchholz) 3 GS / 22.2 IP
So bearing in mind that some of the demotions-in-status (maybe as many as half) were due to injury, your average #6 SP going into the year even on a top pitching team will get ~60-80 IP, your average #7 SP will be a reliever / in the minors half the time and the other half the time will get ~40-50 IP.
Based on that, I'm inclined to agree with the posters saying that we ought to trade one of our surplus starters (locks = Price Porcello Sale, contenders = EdRo Pomeranz Wright Buchholz), because at that usage rate they'd be worth a lot more to another team. But we should keep the other, because we'll need enough quantity at the #6 that it justifies keeping around some quality.
With the uncertainty in the rotation, the players pencilled in as the sixth or seventh starters might pitch more than 100 innings this season.
It's not like there isn't a *recent* precedence for this.
Yeah, all these years of following baseball has taught me that there are ALWAYS problems with your pitching once the season starts. "you can't have too much pitching" is a cliche that's grounded in fact. I cannot recall a team - maybe others can - where they had so much above-league-average pitching talent that a starter got stashed in the bullpen or some guys got stashed in the minors despite clearly having success at the ML level. It just doesn't happen: guys unexpectedly suck, or get injured, on every roster, every year.What uncertainty in the rotation? (...) They can't realistically stash two starters in the bullpen. Only one of these guys can be stashed in the minors, and he's probably the best of the bunch. Something has to give.
Maybe looking at the teams who ended up with a >120 ERA+ the last decade or so would be instructive:
2016 CHC, 128, #s 1-5 all made 29+ starts (!), 6th starter got 5 GS / 38.1 IP
2016 CLE, 122, # 4&5 each made 25 GS, 6th starter got 9 GS / 60.2 IP, 7th starter got 10 GS / 53 IP
2016 WSN, 119, 5th starter made 19 starts, other guys got 6 GS / 44 IP (Lopez), 8 GS / 38.1 IP, and 4 GS / 21.1 IP (Giolito)
2015 STL, 134, #s 1-4 all made 30+ starts, 6th starter got 8 GS / 60 IP, 7th got 6 GS / 31.1 IP, Adam Wainwright got 4 GS / 28 IP
2015 PIT, 121, 6th starter got 11 GS / 63.1 IP, swingman got 8 GS / 71.2 IP
2014 WSN, 124, only fielded 18 pitchers all year (!), 6th starter got 5 GS / 25.2 IP, swingman got 7 GS / 50.2 IP
2013 KCR, 120, 5th starter got 15 GS / 94 IP, swingman Bruce Chen got 15 GS / 121 IP, two prospects got 5 GS (Duffy) and 3 GS (Ventura)
2012 CIN, 123, #s 1-5 all made 30+ starts, 161 between them, damndest thing I ever saw
2012 TBR, 121, #s 1-4 all made 31+ starts, 6th starter got 8 GS / 38 IP, 23yo Chris Archer got 4 GS / 29.1 IP
2011 PHI, 127, Halladay/Lee/Hamels/Oswalt, swingman got 15 GS / 114.2 IP, 7th starter (Joe Blanton) got 8 GS / 41.1 IP
2009 SFG, 120, 5th starter (45yo Big Unit) got 17 GS / 96 IP, 6th starter (Brad Penny) got 6 GS / 41.2 IP, 7th starter 5/30, 8th starter 6/28
2008 TOR, 122, 5th starter got 19 GS / 111 IP, 6th starter got 12 GS / 65 IP, 7th starter 6 GS / 42.1 IP, 8th starter 5 GS / 27 IP
2007 BOS, 123, 6th starter (Lester) 11 GS / 63 IP, 7th (Gabbard) 7 GS / 41 IP including a CGSO, 8th (Buchholz) 3 GS / 22.2 IP
So bearing in mind that some of the demotions-in-status (maybe as many as half) were due to injury, your average #6 SP going into the year even on a top pitching team will get ~60-80 IP, your average #7 SP will be a reliever / in the minors half the time and the other half the time will get ~40-50 IP.
Based on that, I'm inclined to agree with the posters saying that we ought to trade one of our surplus starters (locks = Price Porcello Sale, contenders = EdRo Pomeranz Wright Buchholz), because at that usage rate they'd be worth a lot more to another team. But we should keep the other, because we'll need enough quantity at the #6 that it justifies keeping around some quality.