Leeds United got their first Premier League win in Saturday's 4-3 thriller against Fulham at Elland Road.
Mateusz Klich and Patrick Bamford, along with a brace from Helder Costa, settled the game, the Whites' first Premier League game at Elland Road in 16 years.
Talking to BT Sport after the game, Marcelo praised Fulham for making it difficult for his side, even after going 4-1 down.
"It was a difficult game, it was difficult for us to defend, attack and impose our style onto our opponents.
"In the first half, we allowed them to play out from the back too easily and even though we didn't defend too badly, we couldn't attack.
"After our fourth goal, in a very short amount of time Fulham reduced the scoreline, I think it was more due to them playing well rather than us playing badly. From then on, we played well."
After watching his side score 7 goals in their first two Premier League fixtures against Liverpool and Fulham, Marcelo believes Leeds still have a lot to offer in the attacking department.
"Perhaps at this moment in time we're being very efficient, but we're used to creating more goalscoring opportunities than we are at the moment. We will always try to improve."