Roberto has spoken about the Frenchman's return, as well reflecting on his own side's Champions League progress.
"His return surprised me," the Catalan said at the inauguration of a Cruyff Court in Reus. "I don't think anybody expected it, but they've decided to make Zidane their coach.
"He has brought them many titles, but we have to focus on our own business and on finishing the season off well.
"We're not favourites [in the Champions League], not at all.
"All teams are favourites now.
"Any team can fall, as we've already seen, and any opponent will be difficult.
"Right not we're in the final of the Copa del Rey and in a good position in the league, although there is a long way to go.
"We've gone through in the Champions League, so the dream of a treble is still possible.
"It'd be a dream for us and we'll fight to the end to try to achieve it."