River Plate prepare to take on Flamengo in Lima, Peru, in the Copa Libertadores final on Saturday, and Los Millonarios are hoping to make history by winning the title back-to-back under the tutelage of the Argentine.
The 43-year-old has been with the Nunez based club since June 2014 after the controversial resignation of former head coach Ramon Diaz.
He has won 10 titles since his arrival at the El Monumental Stadium which includes two Copa Libertadores and one Copa Sudamericana.
Gallardo has become one of the best coaches in South American football and has been widely tipped to replace under-fire Valverde at the Camp Nou.
Rivaldo, who played for the Blaugrana from 1997 to 2002, has been absolutely adamant that the former Club Nacional manager might be the right man to replace Valverde.
"Of course I believe he could coach Barcelona.”- the former Brazil international told Betfair.
“He's preparing for that. His work at River Plate has been fantastic. He won the Libertadores last year. “
“He's at the point where he's ready to go to Europe and manage a top side like Barcelona.”
The 47-year-old said Gallardo’s men could become one of the greatest teams if they are able to beat Flamengo on Saturday.
He added: "If River win back-to-back Libertadores, everyone on the planet will be talking about them."