Chelsea has now three opportunities to play against teams that are not in top shape in the Premier League. Perhaps this win against Dortmund now gives them a push and they can improve. If they started a winning streak now of three consecutive games, they would afterwards host the game against Liverpool and that could be their final chance to keep a realistic probability for the qualification for the international ranks in the table. I doubt that they can still make it 1-4, but if they win a lot of games the Europa League could still be achievable.
The thing that must become the main concern is about what strategy that will be used by chelsea. Chelsea is very often used the strategy that didn't suit its players under potter. The leicester city gonna be the next match for chelsea. Chelsea needs to think about which strategy that will be very beneficial for the club. Potter must not put its ego at the top of everything by keep using the garbage strategy like when it was playing against leeds. Potter shall stop to make more and more mistakes. The win against dortmund may save him from being sacked by todd but he is not yet safe if he will not able to make chelsea enter into the top positions of premier league. Chelsea may miss opportunity to play in the UCL next season.