How does this work? Has anybody studied this? How does a pitcher fatigue in-game? Are IP/G a factor? I'm not worried about the implications of the fatigue outside the game, but want to know how far a pitcher can be pushed in a game. When we had LIVE play, you could see the in-game fatigue percentage of the pitcher for every at-bat. You could theoretically leave them in forever, but could tell when they were no longer effective. Hypothetical situation: If I had a 6-man rotation with enough each pitcher having enough innings to pitch 9 innings every game for the whole season, would there be in-game fatigue issues?

IP/G is the only factor.
In *general* for a low K and BB pitcher I give about 12.5 pitches per inning as my limit, for a higher K and BB, 15. These are rough estimates.

For my starters I try to have their IP/G 1 more than I intend to pitch them, so If I have a 4 man rotation and a pitcher has 240 innings, that would be an average of 6 per start, so I'd want him to have at least 7 IP/G, but might be willing to go as low as 6.5.

As Tulsa says, IP/G is only factor... but as we used
to be able to see with LIVE play, even a 9 IP/G does not mean they won’t run into in-game fatigue. From LIVE we could see even the 9 IP/G guys starting to fatigue around the 6th inning to where they dropped to around 70% in the 9th. Lower IP/G began dropping sooner.

Tulsa’s goal of at least 1 inning more than you intend to throw them is wise to minimize the effect, but the effect overall is quite small as long as you stay at or below their IP/G.

So, in-game pitch count has no real affect, just the IP/G? In general, my settings don't usually allow for guys to throw more than about 7 to 7.5 innings, but on occasion, I'll see a guy throw a complete game (usually a shut out,) But if it is based solely off IP/G, wouldn't you be less likely to have a 7 IP/G guy throw a CG shutout or 1-run game because of how the fatigue is structured?

Let's say that I am in a gimmicky league where I expect pitching to seriously dominate. I think it will be commonplace to throw 9 innings in 90 pitches. 90 pitches is where I set a lot of my guys in normal leagues, but that usually only gets me 6.5 to 7 innings. By the descriptions above, my SP will be fatigued because of inning, and not pitch count? Just trying to clarify.

Posted by Area51man on 2/4/2021 12:24:00 AM (view original):
So, in-game pitch count has no real affect, just the IP/G? In general, my settings don't usually allow for guys to throw more than about 7 to 7.5 innings, but on occasion, I'll see a guy throw a complete game (usually a shut out,) But if it is based solely off IP/G, wouldn't you be less likely to have a 7 IP/G guy throw a CG shutout or 1-run game because of how the fatigue is structured?

Let's say that I am in a gimmicky league where I expect pitching to seriously dominate. I think it will be commonplace to throw 9 innings in 90 pitches. 90 pitches is where I set a lot of my guys in normal leagues, but that usually only gets me 6.5 to 7 innings. By the descriptions above, my SP will be fatigued because of inning, and not pitch count? Just trying to clarify.

Ok let's compare 3 situations:

1908 Ed Walsh 7.03 IP/G
2004 Randy Johnson 7.02 IP/G
1890 Tom Ford, Really crappy pitcher with 7.03 IP/G

That 7 translates into some number of pitches, which is how fast/slow the in game stamina drains, this is based on WHIP, K/9 and BB/9, or something similar.
Walsh has low WHIP, Low K and Low BB, ergo his 7.03 will translate to the lowest. I would in my mind assign him 12.5, so I'd probably put him on a 90 pitch limit.

2004 Randy Johnson has higher K thus he would be assigned more pitches, i'd mentally give him about 15, so I'd put his pitch limit at around 100-105.

1890 Tom Ford is horrible, high WHIP, high BB, so he would have the most for his 7. Not that he would ever survive 7 innings, but you get the point.

If Walsh pitches 90 pitches in 5 innings or 26 outs into a shutout, his fatigue level would be the same.

Posted by Area51man on 2/3/2021 11:32:00 PM (view original):
How does this work? Has anybody studied this? How does a pitcher fatigue in-game? Are IP/G a factor? I'm not worried about the implications of the fatigue outside the game, but want to know how far a pitcher can be pushed in a game. When we had LIVE play, you could see the in-game fatigue percentage of the pitcher for every at-bat. You could theoretically leave them in forever, but could tell when they were no longer effective. Hypothetical situation: If I had a 6-man rotation with enough each pitcher having enough innings to pitch 9 innings every game for the whole season, would there be in-game fatigue issues?

From the classic posts by contrarian23, also found in the "FAQ About SIM" Forum at the top of the Forum list:

All about fatigue

Understanding Fatigue
http://www.whatifsports.com/forums/Posts.aspx?TopicID=434633
More on hitting fatigue
http://www.whatifsports.com/forums/Posts.aspx?TopicID=461000
How fatigue works when you pick someone up from the WW or acquire them via trade:
http://www.whatifsports.com/forums/Posts.aspx?TopicID=453991

As Tulsa indicates, it's still driven by pitch count, but that pitch count is solely calculated by their IP/G. If they're burning through innings with less pitches than they are allotted per inning, they'll be able to throw more innings before the in-game fatigue creeps in. You can use elbirdos formula to calculate their total allotment of pitches and divide that by their IP to get a Pitches/IP for each pitcher. Then multiply that by their IP/G, to gauge a theoretical max PC for any game for them to avoid in-game fatigue's full effects. I've seen as lows as 11.3 for quality deadball pitcher and as high as 19.7 for poor modern pitchers from guys I've used/calculated it on. Like Tulsa, I also tend to generally estimate most cases and use 13/16 where he uses 12.5/15.

Thanks, guys. If I paid better attention to this kind of thing, I might have better results over the long haul. I only thought about it because of a theme league I am in that I want to push some boundaries on.