Possibly I should have Mayer and Duran in separate tiers, but overall I think that people are misinterpreting Mayer’s market value - which is not a shot at Mayer, but more a point on what a “top 20ish MI prospect” will return in trade, especially factoring in that - for whatever reason - he has not produced at AA or above.
Based on some research, the only there recent deals I can think of where a similar prospect was moved were the Berrios deal in 2021 and the Castillo deal in 2022 (possibly Chisholm for Gallen, but that was back in 2019). In both circumstances, the similar MI was probably the “center piece” but more like a $5 used with other denominations to get a $10.
Berrios had 1.5 years of control left when he was traded for Austin Martin (19, 22 and 22 on the big three prospect sites) and Simeón Woods Richardson (69 on BA and 87 on MLB). Martin had put up a .779OPS in AA at age 22 at the time of the trade.
Castillo also had 1.5 years left and Marte was certainly the biggest piece in that deal (18, 11, 15) on the big three. He had (similarly) only produced at A+ (.825OPS at age 20). Arroyo was not ranked entering the 2022 season, though he was producing a .900OPS at 18 in A ball. He was probably around #75/80 at that point in time.
The Castillo deal is probably closest in comp to what the Sox could expect to acquire with Mayer as the centerpiece, but they’d almost certainly have to add a Duran or Yorke piece with him to get a good SP and it would likely only be someone with 2 seasons of control. They’d probably have to add some smaller pieces with them as well.
So - again not looking at all at the other team’s roster or farm system, of “mentioned” starters you’re probably talking about possibly Valdez, maybe Luzardo (bc even though he has 3 years left, he’s not as proven as Castillo or Berrios), and possibly Cease. All of which are the types of pieces I’d be on boarding dealing Mayer with a “Duran / Yorke” piece and more to acquire.
If you wanted to go for a younger pitcher, the Jazz Chisholm / Zac Gallen deal is the closest I can think of, but nor an exact comp as Chisholm was more in the 60 range than the 15 range, but Gallen was also kind of an out of nowhere prospect. But to play the game, you miiiiiiight be able to pull a deal like Mayer for Gavin Williams (which I’d certainly do, but seriously doubt Cleveland would).
Something that I think would make sense for both teams would be a Mayer for Tanner Bibee deal. Not that I’ve heard Bibee is at all available, but I could see that being viable on both ends (for what it’s worth, BTV agrees it’s a fair trade).