Mahrez was the subject of a huge saga at the end of the January transfer window, with Manchester City trying desperately to sign the former PFA Player of the Year.
The Algerian superstar has been desperate to seal a transfer from Leicester City to his dream club since the start of the 2017/18 Premier League campaign.
The 27-year-old has signed a five-year contract will wear the No 26 shirt. Pep is committed to playing attacking football, which is a ideal for me, and City's performances last season were outstanding.
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The former Mallorca midfielder made 53 appearances for Madrid in all competitions in 2017-18, netting 11 goals. He was used as a substitute in all three of Spain's group-stage matches at the World Cup as well.
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The FBI agent was accused of firing at the protesters then picking up shell casings to hide that fact and lying to investigators. Dwight Hammond, 76, and his son Steven, 49, were convicted in 2012 and sent to prison on arson charges.
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Chelsea winger Kenedy has undergone a medical ahead of a season-long loan move to Newcastle, sources have told ESPN FC. But Chelsea are always keen to keep hold of their young stars, with many having regular spells away from west London.
City's director of football Txiki Begiristain added: "Riyad is a hugely talented player".
Mahrez's experience of winning the Premier League will certainly have left him hungry for more success, and he now has the chance to achieve that once more under the stewardship of Pep Guardiola. "We're sure he will bring additional attacking quality to our squad".
"In the four and a half years since Riyad signed for the Foxes, he has played his way into the hearts of all Leicester City supporters", a statement read.
Leicester City will face a real fight to keep hold of the no-nonsense defender following the competition and it remains to be seen whether one of the top clubs can entice him out of the King Power Stadium.