I see Virgil van Dijk making a difference to the back four because he is a leader'.
Van Dijk is the Reds' priority target in the final weeks of the transfer window, with the Southampton centre-back having handed in a transfer request this week.
Redknapp said: "I look at that Liverpool back four and there's a reason why they concede so many goals because they're disorganised and they have no leaders at the back".
Stefano Okaka scored with a header at the near-post, after drifting between Liverpool players Roberto Firmino and Joel Matip. What defenders can do it?
'There are two ways of marking at a set piece and Liverpool are terrible at zonal marking, ' Carragher said on Sky Sports, while critiquing Liverpool's defending for the Watford opener.
"The way Liverpool set up, set-piece-wise, they're always going to concede goals".
"I'm saying 100 per cent he would (make a difference)".
But once again Carragher disagreed, he said: "If Van Dijk was playing instead of Lovren or Matip - he would have been in one of their positions".
The two Jamies are certainly fired up for the new Premier League season.
But that just acts like a red flag to a bull for Carragher, who continues to rant and argue with his colleague, as you can see above.
"I don't care who is at centre-back, you can't do that much to stop those goals".
'It's nearly impossible. What defenders can do that?' Van Dijk will improve it, yeah, but one man can't change it all'.
"If you want to challenge for the Premier League, or win the Premier League, you've got to be conceding less than a goal a game: 30, 35 goals".
"It's the setup of the manager, he's been here now 18 months: set-pieces are the worst in the league, conceded the most goals of the top six, there's still no change".
"It's not rocket science how Liverpool concede goals: set-pieces and counter-attacks".
Carragher voiced his concerns after the game, but Gary Neville couldn't help but aim a dig at the former Liverpool defender on Twitter shortly after Watford's equaliser.
"I think Manchester United will be in there, they didn't make the top four previous year but I think they will with the additions that they've made", he said.