The Greece international had been close to joining Premier League outfit Arsenal but he will instead replace Mehdi Benatia at the Stadio Olimpico.Roma has confirmed the signing of Olympiakos defender Kostas Manolas for an initial fee of 13 million euros.
The 23-year-old defender had been on the verge of joining Arsenal but the Gunners' €10 million bid was rejected, thus allowing the Giallorossi to pounce.
"Konstantinos Manolas is now a Roma player," read a Tweet posted on the Serie A side's official Twitter profile on Tuesday evening.
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Roma was in need of a replacement for the Bayern Munich-bound Mehdi Benatia and agreed a fee with Olympiakos - which could could rise to €15 million depending on bonuses - just hours after the Moroccan completed his move to the Allianz Arena.
The Greece international, who could make his debut in Saturday's Serie A opener against Fiorentina at the Stadio Olimpico, has penned a five-year contract with Rudi Garcia's side.