However, the Reds are already looking to make changes and build their squad.
Elsewhere, Jurgen Klopp has dropped a huge hint he will be signing more players at Liverpool after landing Naby Keita and Fabinho. Yet, they still need to strengthen up their shaky back line.
Keown also compared Maguire's presence in the heart of the Three Lions' defence to the legendary Bobby Moore, who lifted the World Cup for England in 1966.
Harry Maguire has become one of the unlikely heroes of England's run to the semi-finals of the World Cup in Russian Federation this summer.
The ex-Reds defender told the Liverpool Echo: "I've been a big fan of Harry Maguire since his days at Hull City".
Rather than the player who anxious about making a mistake against Lithuania in a World Cup qualifier in October past year, the Leicester City defender is now the player who makes the difference.
"I feel like I've settled down into the tournament".
After more goals came from set-pieces in this World Cup's group stage than any other, dead-ball strategy has continued to have a huge impact in the knockout phase, with five of the 11 goals scored in the quarterfinals coming from free kicks or corners. But I think he would be worth it.
Jurgen Klopp spent big on a new centre-half in January, breaking the club's transfer record with the £75 million ($100m) deal with Southampton. He wasn't even guaranteed a starting place in Gareth Southgate's side, but he took his chance well against Tunisia, and since then, he has only got better - or so they say. He's like an English version of Van Dijk.
"Hi Ben, I've seen your video and you are an inspiration", Kane wrote, using the hashtag, #BensWorldCup.
As a youngster he spent much of his time patrolling midfield before transitioning to centre-back in his mid-teens, and those past experiences are serving Maguire well.