The Gunners managed to create some new-found positivity surrounding their top-four challenge earlier this month after Arsenal were 5-1 winners against Everton at The Emirates.
January signing Pierre-Emerick Aubamenyang and Henrikh Mkhitaryan impressed in the north London side’s resounding victory over the Toffees in the Premier League.
However, Tottenham were comfortable 1-0 winners against Arsenal in the derby clash at Wembley on Saturday afternoon following Harry Kane’s headed winner.
Arsenal haven’t had a specialist defensive midfielder in their ranks since Gilberto Silva and Patrick Vieira dominated the middle of the park.
Former Tottenham midfielder Redknapp doesn’t anticipate Arsenal competing for a top-four finish again until Wenger signs a proven defensive midfielder.
“Arsenal can have all the pace they like in attack,” Redknapp told the Daily Mail.
“Until they buy a midfield powerhouse in the vein of Patrick Vieira, they will remain also-rans in the race for the top four.”
Arsenal signed Switzerland international Granit Xhaka in a £33m deal from Bundesliga giants Borussia Monchengladbach in the 2016 summer transfer window.
Xhaka has struggled to make a positive impression at the north London club and has regularly been criticised for his poor disciplinary record.
Arsenal are seven points behind fourth-placed Tottenham with 11 games to go in the 2017-18 Premier League campaign.
The Gunners will take on Manchester City in the League Cup final at Wembley later this month.
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