The London side have only picked up one point in the past three Premier League matches.
After the 2-0 loss away from home on Monday, Maresca spoke about his two center halves having a tough game.
He stated: "I think Liam (Delap) is a bit different to (Dominic) Calvert-Lewin in terms of skills. But I think first-half we conceded a penalty and then we conceded one or two more chances in the same way; long ball for Liam, try to defend the ball and shoot.
"In the second-half, it was copy and paste. Again, we conceded the goal because we unfortunately made a mistake.
“Then they had some more moments, exactly the same; a longer ball for Liam and he fights against everyone and shoots. This is Liam. Liam and Calvert-Lewin, I think they're a bit different."