The Alviverde boss revealed that signing the Argentine would be a coup for the Brazilian club, but insisted that the Verdao are not the only outfit interested in the player
The 34-year-old playmaker has been without a club since leaving the Argentine team in the summer, and has been linked with a number of top teams in South America.
Kleina confirmed that Palmeiras are interested in Riquelme, but warned that the coaching change at Boca could complicate matters.
"Who would not want to have a player of his quality, especially for the Libertadores?" Kleina said to Fox Sports.
"We have to see how the player is as he has not played in a long time. Now that Bianchi, who is a good friend of Riquelme, has returned to Boca, things have become complicated.
"All we can do is wait and hopefully we will welcome him to the club," Kleina concluded.
Boca's Bianchi also reaffirmed his interest in the player, but made clear that only Riquelme knows what follows next in his career.
"We will see what the chances are for Roman to come back. The decision is Roman's. I'll speak with him and see if he is prepared to return.
"I know what Roman can give to the team. However, until I meet with him, I can't say anything else."