"Samir Nasri is currently playing in a friendly with Marseille. Seems to be enjoying retirement," one fan tweeted.
While another added: "Honestly thought that picture of Samir Nasri was fake."
"What the f*** happened to Samir Nasri?" another questioned after seeing the photo on social media.
A fourth added: "Don’t tell me that’s Samir Nasri. Wtf man."
Nasri announced his retirement from professional football last month after spending a year out of the game following an exit from Belgian side Anderlecht.
In his heyday, Nasri was considered one of the finest players in the Premier League – especially at his peak at Arsenal.
A move to Manchester City provided a Premier League triumph, but after leaving City, Nasri served a doping ban that he revealed played a part in his retirement.
"An incident really hurt me and changed my relationship with football: my suspension. I found it more than unfair as I didn't take any drugs," he told Le Journal du Dimanche.
Nasri continued: "After that [leaving Anderlecht], I didn't necessarily have the motivation anymore.
"No challenge really suited me. And I couldn't see myself coming back to France if it wasn't at OM."
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