Spurs have finished in the top four in the last four seasons under Mauricio Pochettino, while Arsenal have failed to qualify for the Champions League in the last two campaigns.
Tottenham failed to make any signings in the 2018 summer transfer window despite their title rivals Manchester City, Liverpool FC and Manchester United all strengthening their options.
Arsenal, on the other hand, added five new players to their squad following Unai Emery’s appointment as Arsene Wenger’s replacement at the end of the 2017-18 season.
The Gunners lost to Manchester City and Chelsea FC in their opening two Premier League games before the north London side eased to victories over Cardiff City, West Ham and Newcastle United.
Tottenham, meanwhile, have lost to Watford and Liverpool FC in their last two Premier League outings before a 2-1 loss to Inter Milan in the Champions League mid-week.
Former Tottenham captain Redknapp believes Arsenal are starting to close the gap on their bitter derby rivals.
“I still feel that Arsenal are a little bit weaker than the other top-six sides, but Tottenham have opened a door for them with their poor summer and their recent form,” Redknapp told Sky Sports.
“For a while, it looked like the gap between the two sides was getting bigger and bigger. Tottenham seemed to be getting further and further away, but they have got too comfortable.
“Their lack of activity in the summer might mean Arsenal do not have to wait long to overtake them again.“
Arsenal haven’t won the Premier League title since 2003-04.
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