The Gunners have only managed to record one Premier League victory in their last six outings to fall off the pace in the top-four race.
Arsenal suffered a 2-0 defeat by Leicester City in their last top-flight outing to fall eight points adrift of fourth-placed Manchester City.
The north London side will welcome a Southampton side with the worst defensive record in the Premier League – they have conceded 29 times in 12 games.
Southampton are winless in their last six top-flight outings following a disastrous run of results that includes a 9-0 loss to Leicester at home.
Former Saints manager Redknapp believes that Arsenal need to beat a Southampton side lacking confidence at The Emirates on Saturday afternoon.
“Arsenal face a crucial home fixture with Southampton knowing only victory will keep them in the chase for a top-four finish,” Redknapp told BetVictor.
“The Gunners find themselves eight points adrift in sixth position and with title hopes almost extinguished will hope to remain in the chasing pack.
“Saints themselves are desperate for points at the other end, of course, after losing three PL games on the bounce and collecting just the solitary point from their last twenty one available.
“Confidence must be extremely low at St Mary’s and Arsenal will fancy their chances to inflict further pain. They are unbeaten on home soil and Alexandre Lacazette and Pierre-Emerick Aubameyang are still the envy of many of their rivals, offering a solid goalscoring partnership.
“There can be no excuses and Arsenal can celebrate the return from the international break with success.”
Arsenal have lost to Sheffield United and Leicester City in two of their last four Premier League games – and the Gunners drew with Crystal Palace and Wolves in their other two fixtures.
The north London outfit are already 16 points adrift of Premier League leaders Liverpool FC after 12 games.
Arsenal signed six new players in the summer transfer window to bolster Unai Emery’s squad ahead of the new Premier League season.
However, the summer signings have failed to significantly improve Arsenal.
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