Sky Sports analyst went on to say that the England international is better than the current two options, Eric Bailey and Victor Lindelof.
United were struggling with a transfer window months later with only Donnie Van de Beek signing.
Ole Gunnar Solskjaer He was very determined to land Jadon Sancho but the Red Devils looked dangerous in the back.
They went to Deadline Day determined to sign the players, with goals by Alex Tillis and Edinson Cavani.
Sancho’s move was set back as Borussia Dortmund was unwilling to negotiate.
But an outgoing one caused a stir when he left Smalling for Rome permanently, after his successful stint there last year.
Redknapp couldn’t understand why the former Fulham star had been allowed to leave given United’s problems at the back.
It was only Sunday when Tottenham He moved to Old Trafford and scored 6 goals in his worst home defeat since 2013.
Manchester United are looking to chart their way back to the top. Ole Gunnar Solskjaer has already brought in Donnie Van de Beek but Jadon Sancho remains the number one goal for Manchester United.
And you can track their journey by subscribing to the amazing new Mirror Football newsletter!
From the latest news reporting to agenda setting stories, get it all in your email inbox.
Registration is simple. Put your email at the top of this article or follow the instructions on this Link.
“If you look at Manchester United on Sunday, you can get a player in every position,” Redknapp told Sky Sports.
“None of these players did anything or showed anything that they wanted to be a player at Manchester United.
“The players have to do much better.
“The interesting thing to me, is that they let Chris Smalling go to Rome.
“I saw Bailey and Lindelof, he went to Italy and he was successful there – I think he’s better than they have.”
This came on the heels of the comments he made Patrice EvraWho was shocked by his former club’s performance against Tottenham.
He targeted the Frenchman Harry Maguire, who made a number of mistakes – including the disastrous start when he pushed Luke Chau to the ground, allowing Tangoy Ndombele to score.
On Sunday he said, “I know you gotta have some filtering when you talk on TV, but that’s a mess.
“Gary Neville heard him say Captain Harry Maguire needs a vacation. We always hear about being paired with someone. But what about getting him out of the team?
“I don’t want to start criticizing the players. I’m someone who has been there. I make a lot of comments about the board but tonight no one has any excuses.”
“They let down all the United fans. I don’t care about it because I was beaten 6-1.
“But almost every year it’s the same story. At the moment I feel like every United fan.
“Extreme organizer. Problem solver. Passionate web buff. Internet expert. Devoted travel nerd. Professional troublemaker.”