What is a designated closer fatigue in ATG?

Since there are no closer ratings what happens when you designate a closer...does it read as a C0?

The pitcher you designate as close will be brought in when HAL's logic says it is time for picking someone with closer role.
The closer rating however is ignored and normal reliever rules for fatigue are followed. So C0 or C6 or whatever is irrelevant and it is just like that pitcher was just R2 or whatever. No special fatigue rules or penalties are imposed.

The pitcher you designate as close will be brought in when HAL's logic says it is time for picking someone with closer role.
The closer rating however is ignored and normal reliever rules for fatigue are followed. So C0 or C6 or whatever is irrelevant and it is just like that pitcher was just R2 or whatever. No special fatigue rules or penalties are imposed.

Thanks. So if I had no bullpen prefs HAL would use Eckersley as the go to closer anyways?
I have Eckersley (R1)as closer with Robinson (R5) as setup. Drago and Ayala as RP and LP specialists. 48 saves in 62 chances. Robinson the workhorse.
http://onlinegames.strat-o-matic.com/team/819571

This team I have no bullpen prefs and have no problem with HAL's closer by committee. 53 saves in 70 chances, innings pretty evenly spaced out.
http://onlinegames.strat-o-matic.com/team/819043

I'm starting Barnstormers for the first time and trying to get accustomed to playing ATG

If you have no bullpen preferences set HAL may or may not use Eckersley as closer. It is possible he may refrain from using Eck early due to the R1 but you could not count on that. Hal being hal might just as likely not use Joe klink early and then toss him in as closer. Or in a blowout Hal might be as likely to turn to Eck in the 6th as not.

If you want Eck to be the guy Hal saves until the 8th or 9th inning and Eck to be the one Hal turns to with game on the line in that situation you should still list him as your closer. I would always list someone as closer. The fatigue C? fatigue rule is not used but the closer role is recognized and used.