Lukaku has made two substitute appearances since being ruled out for a month with ankle trouble.
Chelsea boss Thomas Tuchel, who has been managing the £97.5million striker’s minutes since his recovery, said: “He is in training, he wants to start.
“How difficult is it to reach the top level? It is also difficult for Romelu and the other guys who have come in after injuries to hit their top level.”
Chalobah will have further tests to determine the severity of his injury, meaning Andreas Christensen is likely to continue at centre-back against West Ham.
Jorginho is expected to partner Ruben Loftus-Cheek in midfield, while Timo Werner is also fit again.
Chelsea predicted XI: Mendy; Christensen, Silva, Rudiger; James, Loftus-Cheek, Jorginho, Alonso; Mount, Lukaku, Havertz