When I want to demote an ML player who is out of options I designate him for assignment to open a spot on my ML roster.
This prompts a choice of waivers or no waivers.
Please explain these options.
Thanks.

when you designate for assignment with waivers the player goes through waivers first. If he is not claimed on waivers you can assign him to any team in your system. If he is claimed on waivers he is no longer on your roster. Not sure what happens if you select no waivers since I always select with waivers.

Posted by wylie715 on 8/4/2016 6:04:00 PM (view original):
when you designate for assignment with waivers the player goes through waivers first. If he is not claimed on waivers you can assign him to any team in your system. If he is claimed on waivers he is no longer on your roster. Not sure what happens if you select no waivers since I always select with waivers.

If you select No Waivers, he leaves the ML roster and the 40 man, giving you some flexibility. You then have 10 days (I think) to do something with him, presumably trade him.

If you don't (can't) trade him within 10 days, what happens?

I think he gets Released - similar to keeping a a guy unassigned after you trade for him.

From the Help page:

If a player is on the 40-man roster, he may be designated for assignment. This means he is immediately removed from the 40-man roster and, if necessary, the big league roster . The franchise then has 10 actual days (30 HBD cycles) to make a decision on this player. He may be traded, released or placed on waivers. If he clears waivers, he may be outrighted to the minors (assuming he'll accept the assignment). Players who have been designated for assignment for 7 actual days and are not part of an accepted trade and who have not gone through waivers will be automatically waived. After 10 days, they will be automatically released.

So... the only reason not to waive a player immediately would be if you're actively working to trade him, and you've got one week to do that.

If the player does not accept the assignment to the minors, are you still responsible for his salary even though he becomes a free agent?

You can always waive him during the 10 day period as well. I prefer to DFA, non-waive, see if I can trade, if not I just waive him and we are back where we started from.