Both youngsters starred for England underage teams last week and Maresca insists the pair are in his plans.
"They are both in my plans, for sure," said Maresca. "Shimmy was already with us and played some games last year – he even played some minutes in the Premier League.
"Ryan, for me, is more of a winger. He scored four goals against Germany (in England Under-17s’ 7-5 away win); I even watched that game.
"I was very impressed, but I already knew him because we have one of my staff always watching the second team (Under-21s) since last year. They told me that this guy was very good, so I watched him. I think he's good."
Maresca also took the chance to talk up Reggie Walsh, who made his Blues debut last season at 16 years of age.
He said, "I like Reggie because he is doing things that I am demanding from the other players, but he is doing those things without me asking him to do them.
"So I don’t need to ask him to do something; what he is doing already is what I want from that player. That’s why I love Reggie."