Christopher Nkunku had Chelsea ahead before Wrexham struck twice via Luke Bolton and Jack Marriott. The Blues earned the draw through Lesley Ugochukwu.
Maresca later said, "I think the result is always important but I think in this moment, the most important thing is to judge the performance; especially after two weeks. We started, I was happy first-half, also second-half but we conceded two goals.
"Overall, I'm thinking about players like Wes (Fofana) who played 45 minutes after one year. Like I said, the result for us is always important but in this moment, also we need to judge different things. I'm very happy with the performance.
"In this moment, we tried to build with three and two. First-half with James inside and second-half with Malo inside. It does not matter about the level of the opposition; when they sit back with 11 players behind the ball, it's always difficult to find space and solutions are not easy.
"We tried first-half and second-half. For sure, we did many things we can improve but we started just two weeks ago. Tonight was important to start seeing the identity of the team and the identity is there tonight.
"I'm very happy about the performance in general. In this moment, we started just two weeks ago, it's important that us as the staff and the people can start to see the identity of the team. Tonight it was quite clear.
"For sure we are going to add more solutions. Analysing just the timing we started two weeks ago, I'm very happy."
On Romeo Lavia and Wesley Fofana enjoying minutes, Maresca added: "Absolutely. They are both very important. At this moment for them, it is important to get minutes, to use every training session. I'm very happy, especially for them. For one year without getting minutes, it is difficult mentally. They need a boost, energy and 45 minutes is going to help both of them."