The explanation for the correct answer, which is True, is that according to Rule 3.05(b) in baseball, once a relief pitcher enters the game and throws a pitch, the manager is not allowed to make another pitching change unless the current pitcher is injured. In this scenario, the substitute pitcher throws the first two pitches high over the catcher's head, indicating that he is not injured. Therefore, the manager's attempt to bring in the second baseman to pitch is not allowed by the umpire.