Holding runners?

[TwentySeven]

With a runner on first or runners on first and third, often my first baseman will hold the runner at first, even if it is someone slow like Frank Thomas. I would rather have the first baseman play where they normally would, what defensive setting should I use?

[mvp23]

I have the same question. I sometimes use diffese aligament or positioning. I position them to guard the lines or someting similar.