I agree with BradK that there is the possibility of bad streaks in a game. I too think it's a streak under the hood that can keep snowballing unless you get a "lucky" play behind you to break it up. Even then I think it can still continue.
To me it's like hot/cold streaks and how they can continue to get worse and worse until, let's just go with the batter, finally bloops a single and the cold streak, under the hood, may not stop but it doesn't "grow". Batter puts together two "normal" games and the cold streak ends. Like your one game melt down I don't think there is a setting per se that makes this happen. It is bad dice roll upon bad dice roll having a temporary affect on the P's skill/mood etc. that can lead to the wheels falling off in that game.
How to get out of it? Good question.
In a game meltdown like yours it's harder to have an effect, or even know if what you did did have an effect. What I do is try different things and hope.
First identify that it's all going wrong for the P in the game and get him out of there. Also use pitch around more, especially against a batter with low eye and hope he chases for a K. Or try pitch to contact, especially against a batter with low contact, hoping the ball is hit weakly right at someone. Anything different to try to put a stop to the bleeding. At the end of the day sometimes nothing works because it's just "one of those games".
It's similar to what I do for batters or pitchers in cold streaks. Using a batter as the example, I try to put him into a situation that makes success more likely. IE LHB face RHP, avoiding ace SP's unless he has had previous success against them, while making sure he gets out there to face a team's #5 SP. Get him a hit or two and hopefully break the slump.