The Paraguayan attacker has underlined the importance of the upcoming match against PSG and remains hopeful of reaching the quarter-finals
PSG recorded a 2-1 victory in Valencia on February 12, but Valdez has not yet given up hope of making it to the quarter-finals.
"We know how important this is for the club, to continue participating in European competition," the attacker was quoted as saying on the official Uefa website.
"I think the PSG match will be crucial for us to discover what level we are at. There are only strong teams left in the Champions League now, so we have to show we belong here.
"It will be a nice game and hopefully we can get a result. I think the Champions League is what everyone dreams about."
Valencia take on Levante on Saturday before Wednesday's encounter in Paris.