The pitch was the same. But the condition of the pitch changes due to the dew at night. This happened because BCCI had to organize the Day/Night match due to their broadcaster's request for more TRP.
Yeah. These greedy boards and broadcasters are usually the reason why the pitch conditions change drastically for two teams in the same match making it completely unfair for both of them.
You won't find such an issue in sports like Basketball, Baseball etc in comparison.