Speaking at his first news conference as a Man City player, Mahrez said: "I have always believed that "H" (Harry Maguire) is a very good player, he has shown that since the day he came to Leicester and the season he had past year".
Mahrez, who himself made the move from Leicester to the Premier League champions this summer for a club-record £60m, would not be surprised to see Maguire follow a similar path in the future.
The reward of a starting berth in the three-man England defence comes after being an ever-present for the Foxes during their Premier League campaign, playing every minute of the season as Claude Puel's side finished ninth.
"The Manchester City right back, who has played as part of a three-man defensive unit in Russian Federation, admitted he was deeply disappointed that England's World Cup dream had died". "Players at top clubs always have to face competition for places, it is normal for big clubs to have a lot of great players and City are a big club with a big manager", he explained.
'England did not have an overly hard route to the semi-final but they have overcome every obstacle they faced with some solid performances. I want to be part of this.
Do you think Mahrez will become a vital player for City?
Meanwhile, they have also added Jonny Evans from West Brom, a potential new partner in the defence for Maguire.
"I'm confident I can help the team", Mahrez said.
"I'll give my best to achieve for the club".
Mahrez, who was the 2016 PFA Player of the Year, nearly made the move in January but City refused to pay the Foxes' £95m asking price.
"'The price tag doesn't affect me - fees for players have got very big in the last couple of years". He is happy for me. We didn't think we were going to lose but we did. "If I'd moved sooner maybe I wouldn't have been happy, I don't know". City are a big club and have everything to try to win it. "It's a good thing". I wanted to work under him and to play in this club.