The 2015-16 campaign was nothing short of a nightmare for the London club, as the then-defending champions slumped to a 10th-place finish as Jose Mourinho was relieved of his duties and the team missed out on Champions League football.
But Oscar is positive Chelsea have made the right changes to get back on track under new head coach Antonio Conte, while some positive pre-season performances have only increased the Brazilian's confidence.
"I think we have played better with the 4-3-3 than when we have played 4-2-4, but we have two formations and always we try our best," Oscar told Chelsea's official website ahead of Monday's opener at home to West Ham.
"4-3-3 is better for me because I can score more goals, and also create more and tackle in midfield which I like to do to help the team.
"In the last two games I have scored three goals so I am feeling good, we are ready and now we are all just looking forward to starting the season."
Oscar is particularly enjoying linking up with Diego Costa, as the duo combined well in their final pre-season fixture, a 4-2 win over Werder Bremen.
"We like to play together," Oscar acknowledged. "Every time when we have the ball we come close together to try and link up and create something. This is good for the team and for us.
"4-2 was a bit low I think, we played much better than Werder Bremen and we deserved to score more goals. We missed a lot of chances but it was good because the team created a lot. Everyone played very well."