"It's a big period for Arsenal. Since I was there they haven't experienced a situation like this," said the Brazil midfielder.
"Now they are out of the Champions League places which is very uncomfortable but I'm sure they will pick up points and qualify like we expect.
"It's quite hard for a big club like Arsenal to be so long without a title and the team is also very young.
"They need time and this is the problem at Arsenal - when you are in a big club you don't have much time to grow up and they don't know how to cope under pressure.
"It's hard work for the experienced players to help them in the situation they have.
"But they've got quality and a good manager, Arsene Wenger will do a good job with them."