Chelsea boss Antonio Conte says all new signings will need time to settle down at the club.
Antonio Rudiger and Alvaro Morata have both featured against Arsenal on Sunday but both of them failed to impress against the Gunners.
But the Italian boss says it is normal for players to have a slow start after they change clubs.
"Morata has missed work but that's normal, he has only stayed with us for two weeks," Conte told reporters.
"It's very important for him to find a good physical condition and to understand our idea of football. That's normal. It's the same for Rudiger and for Bakayoko.
"[The penalties?] Courtois is one of the best players to kick a penalty.
"If you have a player that shows you during training to be one of the best, you pick him to shoot a penalty.
"Don't forget also that Morata is a forward and he did the same."
