The Argentine is under pressure to keep his job after a spluttering start to the Premier League season.
But former Tottenham boss Redknapp believes Pochettino's future at the North London club is secured.
"Yeah, absolutely, that is not going to happen," Redknapp told the Daily Mail.
"I don't know if they've overachieved. They should be finishing in the top three with that squad, that's where they should be, there's no doubt about that in my opinion.
"But to get to a Champions League final was great for them. It was great to see them reach the final.
"At the start of the year I really thought Spurs would push Man City and Liverpool a lot, lot closer. Tottenham have got a great team, with Harry Kane, Dele Alli, Son – I thought this could be their year.
"But it's been a disappointing start for them for sure and they need to turn it around quickly, but I still think they'll finish third."