In Situation G, what action is legal for F1 when R2 is on second base?

In the context of Situation G, when the runner is on second base, the action that is legal for the pitcher (F1) is to stretch and come to a stop. This is an acceptable move because it allows the pitcher to simulate a pitch without making any illegal actions that would disrupt the rhythm of the play or provide an advantage to the runner.

Stretching and stopping provides the pitcher the opportunity to gauge the runner's intent and decide whether to make a play or pitch, thereby maintaining the flow of the game. This action does not violate any specific rules about pitching and is commonly utilized in various game scenarios.

In contrast, stepping toward first base or throwing to third after a second stretch may have certain regulations limiting those actions. For instance, stepping toward first base without making an actual play on the ball could be viewed as an illegal motion. Similarly, throwing to third after a second stretch might not be allowed if it creates an unfair advantage or interrupts the standard pitching motion protocol. Thus, the focus on the stretching and stopping option emphasizes the legal flexibility afforded to the pitcher in this specific situation.