illegal player/illegal re-entry

Question
The opposite team at the beginning of a game entered a line-up sheet with a DP on the tenth position. The umpire accepted this line-up sheet and gave a copy to us. When the ninth batter has to come to bat, she didn't appear at the home plate but the DP, on the tenth position did.
When we, after one pitch, appointed this to the plate umpire, he told the scorer to switch those players. This happened in the second inning. So the tenth player on the line-up continued to bat the whole game while the ninth player never came to bat.
My question is "is this a good protest if based on this is a illegal player applying rule 4, sec 4 & 5 ?"
Please let me know a soon as possible and thanks for reacting.

Answer
Hi georgette,

it would be the flex who who be listed in the 10th position not the dp who must be listed 1-9

so you're telling me the umpire said to take b9 and make her the flex and put the flex at b9...you can't do that after the line-up sheet is accepted and official by the PU and it should not have been allowed.

The protest if made properly which is right after the umpire's decision should be a misapplication of the playing rules re the official lineup rules. It doesn't matter about an IP or IB penalty because when the protest is upheld it will be about the lineup switch after it was official.
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