The Ukraine winger has been in and out of the Blues team so far this season under the Italian’s guidance.
While Maresca believes in Mudryk’s ability, he admitted the winger has not learned at the necessary speed.
He stated: "First of all, after Panathinaikos, I think we played Newcastle at home and he played some minutes in the second-half. Then we played Newcastle away and he played from the start. We played United the other day and he played some minutes.
"So he is not playing from the start but he is playing. Probably defensively, also, there are things he needs to improve but him like all the rest."
Asked to be more specific, he added: "On the ball, I think we need our wingers arriving in the box; the goal he scored against Panathinaikos. (The shot that hit) the post from (Pedro) Neto against Newcastle. We want our wingers arriving in the box. That is something they struggled with at the beginning but they are now doing much better.
"On the ball, I always say the same: I like wingers one-v-one but when there is no chance, do not force it; if there are two defenders there, don't force it. Start again. That is something we need to learn how to manage and for sure, defensively, sometimes when you find a full-back like (Tino) Livramento, who is a full-back that attacks a lot, you have to follow. You need both ways, attacking and defending."