Montella, 36, becomes the youngest coach in Serie A and takes the reigns following Ranieri’s tumultuous final fortnight in charge of the Italian side.
Roma suffered four straight defeats in all competitions, the latest coming in a catastrophic 4-3 loss to 10th-placed Genoa despite holding a seemingly unassailable 3-0 lead with less than 40 minutes remaining.
And last week Ranieri, 59, watched his side lose 3-2 to Shaktar Donestk at the Stadio Olimpico in the first leg of their last-16 Champions League tie despite having taken the lead.
Sunday’s disastrous league defeat left Roma lingering in eighth place in Serie A, 16 points behind leaders AC Milan and nine points adrift of fourth-placed Lazio.
Ranieri announced his intention to quit in the wake of the three-goal collapse, with Champions League qualification now a serious doubt for the club.
A Roma statement read: “AS Roma announces it received yesterday evening the resignation of Claudio Ranieri as coach of the first team.
“Following this move, the financial contract with Ranieri, whose deal was coming to an end on 30 June 2011, has ended by mutual consent. Roma wishes to thank Claudio Ranieri for the professionalism shown and the work done [during his time at the club].”
The club moved swiftly to appoint former Roma striker Montella, who hung up his boots in 2009 and has since been working as the youth team coach, on Monday.
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