The Italian left Noni Madueke out of the Aston Villa clash, which the Blues won recently.
However, Madueke was back in the team for a 5-1 thumping of Southampton, in which he scored.
Maresca stated post-game: "With Noni, I have personal relation in terms of he can do much more. He can do much more. The moment he starts to score or assist and is happy, he starts to drop a little bit and the reason why he was not playing is because I do not like the way he trained.
"He has to understand that he has to train every day good. He has to be ambitious. He scored one tonight, he has to go for the second one and the third one. He has to give more assists.
"But overall, he is doing great, he is doing fantastic. He is doing even better in terms of numbers. Noni has to understand he has to work more because he can be much, much, much better."
He then added on the benefits of having a big squad: "But also because there are players in behind that are ready. We have four wingers that are all very good. Pedro and Noni for the right side, Jadon and Misha for the left side and in the moment one of them drops for whatever reason, there is one in behind that is ready.
"Noni is not allowed to drop because Pedro is there and doing fantastic. If Pedro drops then Noni is there. The same thing on the other side. This is what they have to understand if we want to be there or be close for something important."
- Get breaking football news faster with the new Tribal Football app! Download now on iOS and Android to stay ahead of all the latest transfers and football updates. Download now: App Store, Google Play