"I've spent time with him at the training ground to get to know him and he is a very good player and a very good person," said the Spanish midfielder.
"It is just a question of getting to know him. We don't always know the movement that Djibril is going to do. a goalscorer and we have to help him keep his level.
"We spend time on the training ground working on the connection between the midfielders and the strikers. Rafa is working to sort out these problems.
"I'm sure he is frustrated but it takes time, and that is why we are working on it. It will come.
"But that is improving and by working hard here we can know each other better."