The 22-year-old completed his switch from the Bundesliga to the Premier League on Thursday, bringing a protracted transfer saga to an end.
Speculation began to mount that the deal could fall through, with the German club apparently reluctant to allow Schurrle to leave until they had found a suitable replacement.
With the signing Heung-Min Son, confirmed on the same day as Schurrle's move, Leverkusen got their man and enabled Chelsea to get theirs. 
"There was a clear agenda and I was in the loop all the time," Schurrle told Bild following the completion of a transfer that was first mooted before last season.
"Of course I am totally relieved that Bayer made this step possible for me."
The forward will now work under returning Chelsea boss Jose Mourinho and he is relishing the prospect, having had the briefest experience of playing for him during Michael Ballack's farewell friendly in Germany last week.
"He was my coach that evening," Schurrle explained. "He shook my hand and said: 'It is done, you are my player.' That was an incredible feeling. He has a special personality and is cool."
Schurrle's fellow Germany internationals Mesut Oezil and Sami Khedira worked with Mourinho at Real Madrid and both offered the Portuguese manager a glowing reference.
"They both told me that he is the best coach they have ever worked with," Schurrle added.