"Pulisic is in the squad for tomorrow," Lampard said. "He won't start the match because of the injury he has had. It has been a difficult injury. I'm very keen to get him back in there so it is great to have him back, for himself and for the boost he can give the team. He is an important player for us."
Hakim Ziyech is "getting closer" to making his debut following a £36 million move from Ajax but will miss out this weekend due to a knee injury, delaying the prospect of the Morocco international, Pulisic and the club's two most expensive summer signings, Kai Havertz and Timo Werner, lining up together.
"I think they will all bring out the best in each other," Lampard said. "Of course, it is a huge miss for us not to have Christian and Hakim fit at this stage of the season. We are all excited to [see them] start.
"Christian has been here for a year so he doesn't have that bedding in process that was part of last year. Hakim is going to bring something completely different for us and I think they will help compliment, not just Kai and Timo, but the attacking players that we have because again we will need to be able to use different players throughout the course of a season. I'm very excited to have those players fit.
"Timo and Kai don't have necessarily favourite positions but I have a clear idea of where I want them to play. At the moment, injuries have not made that possible and you have to be adaptable in those difficult times."