The Mexican came through at La Masia before moving to Tottenham.
"Barcelona always have a great team, even when they are going through a rough patch as has been suggested," said Giovani.
"They still have great players and, for me, are the best team in the world.
"I guess the league defeat stung their pride a little and now they want to react, as we saw on Wednesday. They could come out with more energy and more anger in this match at home."
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