The 22-year-old will join in the New Year after completing the domestic campaign with current club Universidad de Chile.
“We are closing the deal with Vargas,” Napoli sporting director Ricardo Bigon said on the club website (www.sscnapoli.it).
“The negotiations had already started for some time now and our doctor is going to South America to carry out medical examinations.”
The capture of Vargas comes days after forward Ezequiel Lavezzi was ruled out for four weeks with a thigh injury following Sunday’s 3-1 home defeat to AS Roma.
Vargas is likely to be Napoli’s only recruit in the January transfer window with close-season signings Miguel Britos and Marco Donadel close to returning from long-term injuries.
“I think Vargas will be our only January purchase,” Bigon added.
“Britos and Donadel will recover and we will have the full roster in all departments.”
Napoli, who play Chelsea in the last 16 of the Champions League in February and March, are currently sixth in Serie A, 10 points behind leaders AC Milan.
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