Lampard says the young pair will return to action for Chelsea U23s against Brighton tonight.
"Callum is going to play for the U23s this evening along with Reece James," Lampard said.
"They'll get minutes, which is important now. Callum has been training for a while but there's some issues we need to make sure we're okay with – the actual injury itself.
"He'll need to get match fit so these games are really beneficial for him. They're two young players that are going to be big for this club going forward – we'll be watching."