After the ‘set postseason rosters’ a player of mine gets injured for a long period of time. Is it possible to have a player replace him in the first round and how?

Anyone on the 40-man by the time that of the "set postseason rosters" can replace him. Once the first game is starts of the playoff series, that roster is locked for that series.

What is thea difference as far as injury recovery to put someone on the 15 day and leave them there for 58 days versus put them on the 60?

On the 15 he heals and that's it, no matter how long you leave him there. On the 60 he might get extra recovery bumps depending on the injury and term.

If you change from 15-day to 60-day, will the 60-day period start from when the player first went on the 15-day?

I need to know if transferring a player from the 15-day to the 60-day means the DL period goes (a) 60-days from when he originally went on the 15-day; or (b) 60-days from when the DL transfer was done.

EDIT: Looks like it's retroactive to the 15-day start date. Just tried it and the origination date didn't change. That's good.

Question out of left field. Based on my limited experience, I have been working from an assumption there is something akin to a random number generated (RNG) assigned to various aspects of the game but with a lot of uncertainty regarding where. Could be as fine grained as a particular player on a particular day or for an entire team for a season. Lately, I've been wondering if there is a RNG assigned to each team over each development cycle. So, for example, a team might get a crap RNG for ST, followed by a great RNG when the season starts, then another crap RNG when the next dev cycle concludes. Crazy theory? Knowing a lot of really smart people have been working at this game for a long time, I'm wondering what others have learned or suspect is behind the HBD hood.

Yes, at the bottom of all of this is a RNG(s). But it's likely a more complicated combination of realizations of draws from varying distributions that lead to, using your example, a ratings boost after ST. For example, a ratings boost is likely the product of a bunch of random realizations (good coach = more likely to contribute positively, bad player makeup = more likely to contribute negatively, etc..). This is just my intuition, I obviously don't know any of this for sure.

End of season, waiting for playoffs to wrap up. My teams are done so I'm just setting my rosters up for next season. I've got a few AAA guys on the ML roster who I brought up for the playoffs... and I know they're going to be in the majors next season because I've got a number of old players on expiring contracts. Would I have anything to gain by sending them back down so they start next season in AAA again? Or heck, just leave 'em where they are?

Posted by damag on 10/26/2019 4:48:00 PM (view original):
End of season, waiting for playoffs to wrap up. My teams are done so I'm just setting my rosters up for next season. I've got a few AAA guys on the ML roster who I brought up for the playoffs... and I know they're going to be in the majors next season because I've got a number of old players on expiring contracts. Would I have anything to gain by sending them back down so they start next season in AAA again? Or heck, just leave 'em where they are?

1) Flexibility-- what if you get a trade offer you can't refuse to cover one of those spots? Saves you ~$283K, and a demotion penalty if the trade is during ST.
2) A year of service time if you can keep them down for 20 games.
3) Maybe $16K apiece in salary; I honestly don't know.

I’ve actually never tried - do you not get a demotion penalty after the season is over?

Posted by pray4pro on 10/26/2019 6:39:00 PM (view original):
I’ve actually never tried - do you not get a demotion penalty after the season is over?

I think the minor league playoffs have to be over.

Posted by dedelman on 10/26/2019 5:37:00 PM (view original):

Posted by damag on 10/26/2019 4:48:00 PM (view original):
End of season, waiting for playoffs to wrap up. My teams are done so I'm just setting my rosters up for next season. I've got a few AAA guys on the ML roster who I brought up for the playoffs... and I know they're going to be in the majors next season because I've got a number of old players on expiring contracts. Would I have anything to gain by sending them back down so they start next season in AAA again? Or heck, just leave 'em where they are?

1) Flexibility-- what if you get a trade offer you can't refuse to cover one of those spots? Saves you ~$283K, and a demotion penalty if the trade is during ST.
2) A year of service time if you can keep them down for 20 games.
3) Maybe $16K apiece in salary; I honestly don't know.

This.

I send down every player that is pre-arb at the end of each season. It gives me more flexibility and saves me a little money. Like Dedelman said, you may make a trade where you need the roster spot. You might also sign a FA for cheaper than expected and be able to sign an extra bullpen arm or something with the surplus.

Posted by pray4pro on 10/26/2019 6:39:00 PM (view original):
I’ve actually never tried - do you not get a demotion penalty after the season is over?

I have never had a big league player get a demotion penalty after the season was over. If you send a guy to that is currently in the minors to a lower level after the season, they will incur a penalty.