Gundogan, signed from Barcelona last week, came on with 20 minutes to run in the 4-1 win.
“Yesterday, I trained for the first time with the boys and it honestly feels like I’ve never been away and it feels like home. It’s such a joy,” he said.
“I have so much happiness to play again for this amazing club in front of this amazing crowd with these amazing players. I feel very privileged.
“It’s also emotions. I got a lot of feedback over the last two days, a lot of people messaging me. 99% of them were honestly so positive and emotional. I kind of expected that with a good result today that it would be an amazing day. Luckily it turned out like that.
“I could not have wished for a better start. I’m very proud to be back and to be with the people here with all these memories. Hopefully we can try to make better and new memories for the future.”
“Pep is so demanding. This is exactly what I love and enjoy. Because every year, I feel personally I have to reach my limits and get challenged. That’s one quality that is incredible in him.
“I had a short meeting with him, he showed me a few sequences of play, because since I left he tried to adapt a few details. Hopefully I will get them as quick as possible. I feel very confident and then we will see in what kind of role I will be able to contribute. I’m ready to go and ready to be challenged.”
On the match, he also said: “Conceding the first goal is always tough to take but it is important to keep calm. That’s exactly what we did.
“The team reacted in an amazing way and scored three very quick goals.
“We know how strong we are at home especially when we go ahead by two or three goals, it’s almost impossible for the opposition to come back.
“I think it was a really good game in the end and hopefully we can make it three wins from three before the international break.”