I think we also need to consider what a "developed" relief pitcher represents. Taking 2018-2022, below are the lists of 4 WAR (accumulated as a reliever) pitchers - so an average of one win above replacement per full year (bonus or demerits for 2020 inclusive). I chose 4 WAR because 3.9 WAR is...Matt Barnes, so I felt it was pretty good since the source of the thread was that the last guy the Boston developed like that was Barnes. That produced, via fWAR, 26 names
(Note: This is a hugely inexact process of course, I am just trying to build a sample)
8 of those players played for 1 team from 2018-2022 - the remainder were multi-team guys (we'll get to those 18), Of those eight, two of them (Aroldis Chapman and Felipe Vazquez) were acquisitons after their debut of the team they gained value for - Vazquez accumulated in two years of note. That leaves six players who met all qualifications who didn't play for another MLB team prior:
Chad Green: He is currently rehabbing for Toronto, but from 2017-2021, he was normally a valuable relief cog for the Yankees and his year got cut short in 2022.The Yankees acquired him in a prospect for prospect trade in the post-season of 2015 and he debuted in 2016. This one is a lot more like Whitlock or Winckowski in terms of acquisition timeframe.
Devin Williams - He debuted in 2019 but accumulated much of his value from 2020-2022 for this project and has continued as an elite reliever this year. He was a failed starter prospect - drafted in the second round and played as an SP in the minors for two years before converting in 2019 officially to relief and taking off.
Scott Barlow: He spent much of the 2010s in the Dodgers minor league system as a sixth round pick and SP prospect who looked like he had some hope in AA but never could make it above that. KC picked him up as a minor league free agent, swapped him to RP, where he provided decent value in 2018-2020 and much stronger RP performance in 2021-2022. This year has been bad.
Jose Leclerc - He built his place on this list off of a great 2018 and a decent 2019, and has settled in as an alright reliever from there. The thing on Leclerc is that he was signed as a 17 year old IFA in 2010, and debuted in 2016, and only began adding value in 2018. That is an eight year run to get to that point. He was briefly tried as an SP but is one of the purer RP prospects on the list, but it was a very long process to get there.
Seth Lugo - He was a very late round draft pick of the Mets who did well but got rocked in AAA. The Mets plated him as an SP in 2017 and he was alright and had value, then they moved him to the pen where he was a lot better but had fewer innings
A.J. Minter - This is probably the closest pure RP success story. Atlanta took him in the second round and pretty much immediately put him into the RP role - he's never started in the minors. He hit the majors two years after being drafted, had some up and down years and has settled into being quite a decent relief pticher - not amazing but perfectly good
Now for the other 18 names, a handful are long term relief RPs who had 3+ teams - Taylor Rogers, Raisel Iglesias, Adam Ottavino, Collin McHugh, Dylan Floro, Chris Martin, and Brad Hand. In the interest of time it's probably not worth pursing these leads for the homegrown value RP project except Taylor Rogers (converted starter right before he got called up). For the other 11 with two teams
Liam Hendricks - SP with Minnesota converted to RP with Toronto earning that WAR with Oakland and Chicago much later
Edwin Diaz - Interesting one, he was a "failed" starter prospect but he was pretty good in the minors relative to other failed starters, Seattle converted him and his skills took off - the Mets acquired him in the Robby Cano/Jarred Kelenic deal
Josh Hader - Converted starter right before call-up and acquired via trade from the Oroles for Bud Norris with other stuff.
Ryan Pressly - Earned the value in Houston after being a worse reliever in Minnesota for five years.
Giovanny Gallegos - Developed by the Yankees, acquired by STL after his debut in the Luke Voit trade.
Blake Trienen - Came up as an SP, converted to the pen, acquired by Oakland from Washington and has earned value in Oakland and LA.
Kenley Jansen - Don't really need to recap him, one of the best RPs of the generation, stayed in LA for ages - as pure an RP prospect as you can imagine and the poster child for it really.
Kirby Yates - Bounced around to several teams before SD extracted two very good years from him, and then turned into a pumpkin.
Emmanuel Clase - Acquried by Cleveland in the Corey Kluber trade form the Rangers who acquired him in a trade from the Padres - mostly an RP in the minors
Hector Neris- Accumulated the value for PHI and HOU, took a couple years to start being good for Philly from his call up which was four years from his signing - mostly an RP in the minors.
I think you look through this and the trends are pretty obvious. You do have a small handful of homegrown, intentionally developed relief pitchers (Jansen, Minter) and some other focused RP prospects acquired reasonably, but the vast majority as SPs who served better out of the pen, reclamation projects and cheap trade targets from other teams, or proven FA signings. It's really not something that happens as often as we think it will. Now, will Felix Bautista show up on this list some time soon? Probably. But with the volatility of RP value year over year and the resources needed to develop a guy, and the success of downtiering SPs instead, I think teams are very particular at identifying pure RP prospects who are good enough to be impact guys in the bigs but whose arm or stuff won't survive a second time through the lineup. Relief value is heavily variable over years except for the elite of the elite and very few teams have even one of these kinds of guys who are homegrown and eating up good innings at the end. And in some cases, you particularly try to do that by drafting a relief stud real early and bringing him up like that and its just a big waste of resources.
Now as the 80-90 IP RP/Swing Guy comes back into vogue or co-starters become a more regular thing, that might be something teams could look at more to add value, especially as good RP prices are very high, but I find it hard to criticize Sox management for this most teams really don't invest in pitchers targeting lights out relief guys. Bloom is doing what a lot of smart, successful teams have done - target guys who may not be in their best role and move them there or look for undervalued players and get them in house. In the case if Kenley, it was pay out the nose, but in other cases it's those low value player swaps or taking a guy off the scrap heap and fixing a mechanic.
Edit: There's also the element that merely eating innings has huge value. If you ranked Nick Pivetta on this list - with two years as an SP and two split seasons, even with no value in 2019 or 2023, he'd be in the Top 10. Even a middling SP who can put in some value in RP is likely to mean more to a club than a good reliever.
(Note: This is a hugely inexact process of course, I am just trying to build a sample)
8 of those players played for 1 team from 2018-2022 - the remainder were multi-team guys (we'll get to those 18), Of those eight, two of them (Aroldis Chapman and Felipe Vazquez) were acquisitons after their debut of the team they gained value for - Vazquez accumulated in two years of note. That leaves six players who met all qualifications who didn't play for another MLB team prior:
Chad Green: He is currently rehabbing for Toronto, but from 2017-2021, he was normally a valuable relief cog for the Yankees and his year got cut short in 2022.The Yankees acquired him in a prospect for prospect trade in the post-season of 2015 and he debuted in 2016. This one is a lot more like Whitlock or Winckowski in terms of acquisition timeframe.
Devin Williams - He debuted in 2019 but accumulated much of his value from 2020-2022 for this project and has continued as an elite reliever this year. He was a failed starter prospect - drafted in the second round and played as an SP in the minors for two years before converting in 2019 officially to relief and taking off.
Scott Barlow: He spent much of the 2010s in the Dodgers minor league system as a sixth round pick and SP prospect who looked like he had some hope in AA but never could make it above that. KC picked him up as a minor league free agent, swapped him to RP, where he provided decent value in 2018-2020 and much stronger RP performance in 2021-2022. This year has been bad.
Jose Leclerc - He built his place on this list off of a great 2018 and a decent 2019, and has settled in as an alright reliever from there. The thing on Leclerc is that he was signed as a 17 year old IFA in 2010, and debuted in 2016, and only began adding value in 2018. That is an eight year run to get to that point. He was briefly tried as an SP but is one of the purer RP prospects on the list, but it was a very long process to get there.
Seth Lugo - He was a very late round draft pick of the Mets who did well but got rocked in AAA. The Mets plated him as an SP in 2017 and he was alright and had value, then they moved him to the pen where he was a lot better but had fewer innings
A.J. Minter - This is probably the closest pure RP success story. Atlanta took him in the second round and pretty much immediately put him into the RP role - he's never started in the minors. He hit the majors two years after being drafted, had some up and down years and has settled into being quite a decent relief pticher - not amazing but perfectly good
Now for the other 18 names, a handful are long term relief RPs who had 3+ teams - Taylor Rogers, Raisel Iglesias, Adam Ottavino, Collin McHugh, Dylan Floro, Chris Martin, and Brad Hand. In the interest of time it's probably not worth pursing these leads for the homegrown value RP project except Taylor Rogers (converted starter right before he got called up). For the other 11 with two teams
Liam Hendricks - SP with Minnesota converted to RP with Toronto earning that WAR with Oakland and Chicago much later
Edwin Diaz - Interesting one, he was a "failed" starter prospect but he was pretty good in the minors relative to other failed starters, Seattle converted him and his skills took off - the Mets acquired him in the Robby Cano/Jarred Kelenic deal
Josh Hader - Converted starter right before call-up and acquired via trade from the Oroles for Bud Norris with other stuff.
Ryan Pressly - Earned the value in Houston after being a worse reliever in Minnesota for five years.
Giovanny Gallegos - Developed by the Yankees, acquired by STL after his debut in the Luke Voit trade.
Blake Trienen - Came up as an SP, converted to the pen, acquired by Oakland from Washington and has earned value in Oakland and LA.
Kenley Jansen - Don't really need to recap him, one of the best RPs of the generation, stayed in LA for ages - as pure an RP prospect as you can imagine and the poster child for it really.
Kirby Yates - Bounced around to several teams before SD extracted two very good years from him, and then turned into a pumpkin.
Emmanuel Clase - Acquried by Cleveland in the Corey Kluber trade form the Rangers who acquired him in a trade from the Padres - mostly an RP in the minors
Hector Neris- Accumulated the value for PHI and HOU, took a couple years to start being good for Philly from his call up which was four years from his signing - mostly an RP in the minors.
I think you look through this and the trends are pretty obvious. You do have a small handful of homegrown, intentionally developed relief pitchers (Jansen, Minter) and some other focused RP prospects acquired reasonably, but the vast majority as SPs who served better out of the pen, reclamation projects and cheap trade targets from other teams, or proven FA signings. It's really not something that happens as often as we think it will. Now, will Felix Bautista show up on this list some time soon? Probably. But with the volatility of RP value year over year and the resources needed to develop a guy, and the success of downtiering SPs instead, I think teams are very particular at identifying pure RP prospects who are good enough to be impact guys in the bigs but whose arm or stuff won't survive a second time through the lineup. Relief value is heavily variable over years except for the elite of the elite and very few teams have even one of these kinds of guys who are homegrown and eating up good innings at the end. And in some cases, you particularly try to do that by drafting a relief stud real early and bringing him up like that and its just a big waste of resources.
Now as the 80-90 IP RP/Swing Guy comes back into vogue or co-starters become a more regular thing, that might be something teams could look at more to add value, especially as good RP prices are very high, but I find it hard to criticize Sox management for this most teams really don't invest in pitchers targeting lights out relief guys. Bloom is doing what a lot of smart, successful teams have done - target guys who may not be in their best role and move them there or look for undervalued players and get them in house. In the case if Kenley, it was pay out the nose, but in other cases it's those low value player swaps or taking a guy off the scrap heap and fixing a mechanic.
Edit: There's also the element that merely eating innings has huge value. If you ranked Nick Pivetta on this list - with two years as an SP and two split seasons, even with no value in 2019 or 2023, he'd be in the Top 10. Even a middling SP who can put in some value in RP is likely to mean more to a club than a good reliever.
Last edited:
