What happens when a fielder holds a runner from advancing while the ball is in play?

When a fielder holds a runner from advancing while the ball is in play, obstruction is called. This rule applies when a defensive player impedes the progress of a runner who is attempting to advance to the next base. The act of obstruction occurs when the fielder is not making a play on the ball and physically blocks the runner's path, which can affect their ability to advance safely.

In this situation, the umpire would typically recognize that the runner was hindered in their attempt to move forward and signal for obstruction. The runner is then typically awarded the next base if the obstruction impacted their advancement. This rule is intended to ensure fairness and protect the rights of runners on the base paths.

The other options do not apply directly to the scenario described; they involve different situations in the game and do not specifically address the act of a fielder holding up a runner in the context of obstruction.