After selling Gareth Bale to Real Madrid for a world-record £86 million fee, the north London club re-invested the funds into eight new signings ahead of the current campaign, with Roberto Soldado, Erik Lamela and Paulinho commanding the biggest transfers fees of the new recruits.
But former midfielder Redknapp feels only Eriksen has proved himself a worthy newcomer at White Hart Lane, suggesting that most of the other deals had "back-fired."
"Only Christian Eriksen is worthy of his place at the moment and most of the other deals have back-fired," he wrote in his Sky Sports column ahead of the north London derby.
"They had one superstar player last season who was doing incredible things week-in, week-out and at the moment you look around and think 'who is going to do that?'"
So where are they now?
Christian Eriksen: Redknapp's praise of the Dane is understandable, as he has often looked Tottenham's only creative threat in big games. Despite being overlooked the majority of the time by Tim Sherwood, Eriksen has scored three times in both the Premier League and Europa League, also making five assists in the league and in Europe.
Roberto Soldado: Spurs' most expensive signing last summer, Soldado simply hasn't shown up this term. The 28-year-old has only scored five goals in the Premier League this season - hardly a handsome return for a £26 million striker - and any upturn in form may come too little too late this term for Sherwood's men.
Paulinho: Certainly one of Tottenham's better signings, the Brazilian has often impressed, scoring four times and making two assists in the Premier League. The White Hart Lane faithful will still want more from the midfielder, however, as he has not always consistently delivered.
Nacer Chadli: The Belgian has, quite simply, not lived up to expectations in north London. Chadli has scored once and made two assists in the league - but, in 17 games, that has not been good enough. Often ridiculed for his lacklustre performances in a Spurs shirt.
Vlad Chiriches: The defender has done well for Tottenham at times this season but a long-term injury has kept him out of action in recent weeks. With their defensive struggles, Spurs have perhaps been unlucky with this particular signing.
Ezekiel Fryers: Spurs' defensive struggles have been well documented, with Michael Dawson, Kyle Naughton, Danny Rose, Jan Vertonghen, Younes Kaboul and Kyle Walker all having their faults at the back this season. But few have impressed less than Fryers, who is often the aim for much supporter criticism.
Etienne Capoue: Has fallen out of favour at White Hart Lane after some terrible defensive performances. Was played both in midfield and at centre-back earlier in the season and failed to impress in both.
Erik Lamela: For a talent that promised so much, Lamela has been exceptionally underwhelming during his time at Spurs. As such, the winger has only made nine Premier League appearances, while his Tottenham future looks very uncertain.