Chelsea manager, Maurizio Sarri, has revealed why the Blues could not beat Frankfurt in the first leg of their Europa League semi final on Thursday.
The Italian said his team made a mistake in the first 20 minutes, adding that the Germans were very dangerous in counter-attacks.
Sarri said that Chelsea "deserved to win" the game away in Germany.
Pedro scored a crucial away goal for Chelsea as they drew 1-1 with the Bundesliga side.
Luka Jovic had put the home side ahead in the 23rd minute with a fine header.
Sarri told BT Sport, "We made a mistake in the first 20 minutes because my feeling from the bench was that we were playing to manage the result for a 0-0, but we are not able to do it for [our] characteristics.
"Then we started to play after 25 minutes and we played very well until the 85th minute and in my opinion, we deserved to win for the number of good opportunities. For 70 minutes, we were in full control of the match.
"But they are very dangerous because in counter-attacks, if you give them spaces, they are very dangerous. One away is not so bad, they are very dangerous at home but unfortunately, they are very dangerous away. I have seen all the matches in the Europa League on Eintracht and they are also very dangerous away.
"So it depends on the second leg, we have to play at Stamford Bridge, we want the final but we know very well that we have to play a very good match in the next week."