Arsenal manager Arsene Wenger has said that Wojciech Szczesny is his first-choice goalkeeper.
The Poland international was at fault for the only goal Southampton scored against the Gunners in their 6-1 defeat at the Emirates on Saturday.
"Wojciech is number one unless I change my mind," Wenger told Arsenal's official website. "That is clear. That's why he came back in goal.
"You cannot change a goalkeeper every time he makes a simple mistake, because then you have three bad keepers. The confidence is needed.
"It's a special position where confidence is needed. Maybe he put himself a little bit under pressure because he knows [Vito] Mannone played well at Stoke and at Liverpool. I think he played better in the second half."
Arsenal are currently third in the Premier League table with eight points from four matches.
