another line up card question

[BlitzkriegBob]

The only instance in which I would be concerned with the DP entering to play defense would be if she was going in to pitch or catch, so that I can know she would be eligible to have a courtesy runner, or if she was going in to play defense for the flex. The player being replaced on defense is not considered to have left the game, so there is no substitution, unless it is the flex.

As to your second question, she can enter to play defense for someone different every inning if the coach so desires. As long as the DP is batting, and the flex is playing defense, there are no substitutions, so the DP is not "reentering" since she never left the game.