Barca snapped Mathieu up from Valencia for €20 million (£17m/$24m) seven years ago, tying him down to a four-season contract.
The Frenchman won plenty of silverware during his time in Catalonia but never managed to establish himself as a regular in the starting XI, and has now revealed that he would have preferred to continue his career at Mestalla.
What's been said?
“I didn't want to go to Barca. When the club asked me, I was captain in Valencia, I was enjoying my life there and I was wondering: am I going to polish the bench in Barcelona?" Mathieu told L'Equipe.
Mathieu's record at Barcelona
Mathieu picked up nine trophies during his three-year spell at Camp Nou, including two Liga titles and the Champions League.
The one-time France international made 91 appearances across all competitions for Barca, scoring three goals, but only started 47 games in La Liga.
He left Camp Nou in 2017 before joining Sporting CP on a free transfer, and won three trophies with the Portuguese club before retiring due to a serious knee injury last year.