Gusto and his fellow non-internationals were beaten in a friendly against an U21 team last week, which saw a furious Maresca cancel a scheduled day off.
The French fullback revealed: "I don't know what you've seen, it was just normal, we have to fight in training and that's what he said.
"Nothing crazy happened but we just have to continue in this way. That's how we won against Spurs because we trained well this week and we have to maintain that. That's why we work every day, we're trying to create something as a team to win games because every team that's behind us is pushing.
"Our target is to finish in the top four, we don't have to hide, we just have to show our best and keep fighting and that's how we will achieve it. Now we have an important game against Brentford and need to continue showing our togetherness."