"It's been very difficult for me. I'm coming from two or three seasons of doing well, but I was one of those players who got injured at the start of the season," Oscar told Sky Sports.
"(The new manager's arrival) is great for the players. Obviously you have to prove yourself... It will be a breath of fresh air to the team and everyone's excited to prove their worth to be here.
"I haven't been very happy because I haven't been playing very much but, with the new coach coming in, it's a fresh beginning for everyone."
With 35-year-old captain John Terry likely to depart at the end of the season, Oscar paid tribute to his team mate.
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"His future is down to him and Chelsea to decide what's best. Obviously I want him to stay but it's down to them," Oscar said. "He's a great leader.. he will know what's best for his future and whatever he decides I'll be happy for him."
Guus Hiddink's men face Liverpool at Anfield on Wednesday and bring an end to their woeful campaign when they host champions Leicester City on Sunday.
(Reporting by Shravanth Vijayakumar in Bengaluru)
