Roma will pay €3 million for Nainggolan to play the rest of the season on a temporary basis and €6m to sign midfielder on a permanent deal. His contract will run until 2018. Juventus, Milan and Napoli have all reportedly shown an interest in the Belgian international prior to him putting pen to paper with Roma.
Roma enjoyed a stellar start to the season under new coach Rudi Garcia, setting a Serie A record of ten opening wins to underline their title credentials before a series of draws saw them slip behind leaders Juventus. Champions Juventus currently have an eight-point lead over Roma, following La Vecchia Signora's 3-0 victory over the second-place side on Sunday, with Napoli a further two points off the pace.
Nainggolan, born in Belgium to an Indonesian father and Belgian mother, has played four times for his national side and is contention to be a part of his country's 2014 FIFA World Cup Brazil in June.