What action should an umpire take if a pitcher's cap frequently falls off during a game?

In situations where a pitcher's cap frequently falls off, the appropriate action for the umpire is to instruct the defensive coach to ensure the cap is secured properly. This decision helps to maintain the flow of the game while also addressing a potential safety concern. A well-fitted cap reduces the risk of distraction for both the pitcher and the batter.

By working collaboratively with the coach, the umpire encourages the team to take responsibility for their player's equipment, promoting good sportsmanship and care for the game. This approach helps to avoid disruption to the game and allows the pitcher to focus on their performance without the constant worry about their cap falling off.

Other options would not adequately solve the issue at hand, such as removing the pitcher entirely which would be an extreme response, or ignoring the problem altogether, which could lead to further distractions. Giving a warning to only the pitcher does not address the underlying issue of the cap's fit and could lead to repeated occurrences. Thus, guiding the coach to assist in securing the cap is the most effective and reasonable approach.