Waddle questioned the transfer activity of Tottenham manager Mauricio Pochettino on Friday, arguing he did not improve the squad at White Hart Lane and was remiss in not signing a central defender.
Of the six players Pochettino signed heading into the 2014-15 season - after arriving himself from Southampton - only Eric Dier has started in the Premier League.
While Tottenham have the equal second-best defence in the Premier League this season (seven goals conceded in as many games), Waddle has declared the London-based club have not looked strong in the centre of their back four since former skipper King retired at the end of 2011-12.
"I don't think they've had a good pairing at centre-half since Ledley King played," Waddle told the Evening Standard.
"Every game I watch Tottenham play, [Hugo] Lloris seems to be called into action every two or three minutes, so there's got to be a problem if you're goalkeeper makes too many saves."
Waddle thinks Tottenham's defence is holding them back with Pochettino's men sitting sixth in the league ahead of Saturday's clash with reigning champions Manchester City.
"If they can sort out the back two there is no reason they can't challenge [for the top four]," he said.
In the close season, Pochettino brought in full-back Ben Davies, goalkeeper Michel Vorm, Dier - who has predominantly played at right-back, full-back DeAndre Yedlin - who has been loaned back to Seattle Sounders, central defender Federico Fazio and midfielder Benjamin Stambouli.
The four defenders have played an average of 19 minutes each per game in the Premier Laegue, with Dier managing 515 of the total of 533.
"I think he's [Pochettino] got a lot of players very similar to what was already there, there are a lot of players who can play the same role," Waddle said.
