Arsenal boss Arsene Wenger feels they've underperformed this season.
Victory at Southampton would lift Arsenal back into the top four and leave them within striking distance of third-placed Manchester United.
"I believe that there is a deficit between the potential we have shown and the number of points we have, that is what we want to get right," said Wenger, whose side begin their FA Cup defence against Hull on Sunday.
"Now it is time to catch back the points that we lost now until the end of the season.
"I feel we were very, very unlucky with the injuries we got, but with the number of injuries we have had, we have survived quite well.
"I feel it is nearly impossible that we will have the same bad luck on the injury front that we had in 2014.
"I believe that hopefully in the second part of the season, we will have more stability, especially defensively, to be more consistent."