Both youngsters played their first games of the season for the Carabao Cup win over Grimsby.
Lampard said, "They're in the squad and they performed well the other day. Delighted for Reece to get his first goal, Callum to get his goal.
"They still have improvement, they're young players but they've shown the quality that they have. Now they're back fit, they're pushing."
Lampard also gave an injury update.
“Tony (Rudiger) has got a recurring injury in his groin area so we're trying to find a solution because he's still got some pain. We're hopeful it won't be long but I haven't got an end date.
“Andreas (Christensen) should be OK. He's trained with us today. He's missed most of the week. There's still a tiny bit of pain but it's hopefully not a risk, so he'll be in the squad.
“It's been a difficult week for him because his illness left him pretty week. He's been getting a bit of strength back this week so it'll be touch or go as to whether he's involved tomorrow."