Jeremy Mathieu has said he has a point to prove to Barcelona president Josep Maria Bartomeu and sporting director Robert Fernandez over the way his summer exit from the club was handled.
Mathieu, 33, who spent three seasons at the Camp Nou, left for Sporting Lisbon on a free transfer.
The defender faces his former club in the Champions League at the Estadio Jose Alvalade on Wednesday and was asked whether he would celebrate a goal against them.
He told Marca: "I have a lot of respect for my former teammates and the fans.
"If I celebrate, it will be because of Bartomeu and Robert Fernandez, because the way they treated me made things really difficult.
"It was just those two. But that's football, and I'm happy now. I'm not bothered any more."
In a separate interview with Esport3, he claimed Fernandez had made the decision to move him on without the knowledge of coach Ernesto Valverde.
"Robert told me he wasn't counting on me," he said. "I wanted to talk with Valverde. I called him, but he thought that I wanted to leave."
Mathieu, who scored a free kick in Sporting's win over Tondela, added: "I played a lot at Barca, I won titles, and the only thing that hurts is that people say I didn't play much.
"In the first season I played 58 percent of matches and I scored important goals. In the second season a little less, around 54 percent, which was also fine.
"But in the final year things were difficult, with injuries and a lack of confidence from the manager.
"The problem was that Luis Enrique didn't talk with the players much and I didn't know what to do to play more."
Mathieu's final game for Barcelona came against Juventus in last season's Champions League defeat in Turin, when he was taken off at half-time.
He feels he was made a scapegoat, claiming that newspaper Diario Sport "always had something bad to say about me."
"Football is a team sport, and when you lose, it's never one person's fault," he said. "I've watched the game against Juventus again and everyone says that I was the problem.
"It's true that in one of the goals I'm one-on-one and I'm backtracking, but after that there's a pass and you could ask what [Javier] Mascherano or [Gerard] Pique are doing, but no. That's my opinion."