Arteta was keen to stress how much the 34-year-old has meant to him and the club during their time together.
“When you get to the know the person, his background where he was raised in Brazil and what he has done to get to this point it's remarkable," he said. "You understand a lot of things that happen for a reason. It's not just an ability, determination and many other factors.
"I really enjoyed it and learned from him. He has been very helpful all the time with the team. I feel sadness. You get attached to the players emotionally.
"The player we have to get the maximum out of and then there is the person, when it gets to this stages it tough and it hurts because that relationship will be going away when I wont see him everyday. I have to say thank you to him."