Arsene Wenger admits it is ''unacceptable'' to see Arsenal captain William Gallas pictured with a cigarette - but backed the veteran Frenchman as the right man to lead the young Gunners.
Centre-half Gallas, who is set to return following a thigh injury for the Barclays Premier League clash at West Ham on Sunday, was snapped as he left a nightclub in the early hours holding a cigarette in his mouth, although it was not lit.
The former Chelsea defender himself accepts he has put in some ''tired'' performances this season and needs to raise his game to lead the Gunners forwards.
The 31-year-old was perhaps a controversial choice to succeed legend Thierry Henry as Arsenal's permanent captain.
Last season, he famously lost composure at Birmingham when he broke down in the centre circle.
Despite weighing in with some crucial European goals in the current campaign, Gallas has at times been found wanting in defensive duties, particularly from set-pieces.
Yet the veteran defender has always received the support of his manager, who sees Gallas as crucial to the development of the youngsters in the squad.
However, Wenger made it clear if the reports of smoking are eventually substantiated, he will take stern action.
''I didn't see the picture. I have been informed, but I don't like that,'' he said.
''I will check that with him. He has a responsibility as captain of Arsenal Football Club. That cannot be accepted.
''It is a public job with a public responsibility and therefore it is exactly the same for everybody.''
Wenger, though, maintains Gallas cannot be faulted for commitment to the cause.
''I believe that William has a very fair assessment of his performances,'' said Wenger.
''William has worked very hard to come back from his injury and looks very sharp now.
''He has learned a lot. He has taken a lot of criticism, of course, but I think he took it in a positive way.
''He has learned a lot and he himself has come out and said, 'I made a mistake last year and I will change and re-address my attitude.'''
Wenger added: ''I believe he has got a lot of unfair critics and therefore I believe the fact that he could take it and he is still as motivated.
''What you can never fault with William is the motivation.
''He wants to do well, he wants his team to win and he has made a mistake - who didn't? Even great captains, we all make mistakes.''