The Three Lions lost their opening match of the 2014 tournament at the hands of Italy on Saturday, but their performance was widely regarded to be one of their most promising in recent times.
However, Redknapp described suggestions that the current group of players are England's best for years as "nonsense", hinting that he thought the centre-back partnership of Phil Jagielka and Gary Cahill was a weak spot.
"I've heard a few people say that this is the best England side we've had in recent years, but that's nonsense," Redknapp wrote in his blog for 666 Bet.
"It's a good side, but no disrespect to Phil Jagielka and Gary Cahill, they're not in the same league as John Terry and Rio Ferdinand when they were in their prime. We had a stronger side in South Africa."
Redknapp was among the favourites to be named England manager in 2012 before Roy Hodgson was awarded the job.