I've never seen that play before. If I were to guess, it would have to be if the ball is bunted to F5 but I don't like that as F3 has to run in front of a throw from F5 or she would have to go around F5. What I see often is that if the ball is bunted to F5 or F1, and F2 would cover 3B. I see this at the HS and higher levels of play. I remember in 12u/14u, coaches would always be reminding F5 and F1 to cover 3B if they were not fielding the bunt.So can someone explain the scenario where f3 runs straight to 3rd and f4 covers 1st? It was shown on here awhile back and they got the runner going from 1st to 3rd. Seems like it would be a good option anytime there is a runner at 1st and the batter bunts. By explain I mean when would you use that defense versus something else.