The Paraguayan, who is owned by Uruguayan side Deportivo Maldonado, has returned to the club after Roma opted not to pay the €4 million fee to purchase the right-back.
Transfer speculation surrounding Piris has been building since returning from his loan spell in Italy, with Parma and Boca Juniors both showing interest in the 24-year-old.
However, it is the Argentine side that look to have the upper hand in signing Piris after it was reported that he would prefer to sign with the Xeneizes.
“It would be a dream to play for Boca,” Piris told the Argentinian media.
“All my friends are pushing me in that direction”.
“I have played for Roma and Sao Paulo and I think I have the right experience to play with the Argentine club. I’ll see what happens”.
Piris made 29 appearances for the Giallorossi last season, and featured as a first choice defender for most of the campaign.