Ziyech was happy to see action, but frustrated with the result.
He told chelseafc.com: "I was very happy about it (his debut), but it wasn't the debut we all hoped for.
"In the first-half we began well, two big chances and we went up two zero. But then a little disappointing they scored before halftime.
"Then obviously 2-2, then 3-2, then they scored in the last minute and that's not something you can be happy about."
Ziyech continued, "Of course, it will take time (to adapt). But we don't have time because the games are coming really quick. So we have to learn quick. But this can't happen. A last minute goal, it can't happen."