The Catalans' No.1 has come under-fire from sections of the media following a series of high-profile blunders.
But speaking ahead of the match, the Venezuelan gave his backing to the 30-year-old in succinct fashion.
"Doubting Valdes is like doubting your mum," he stated to reporters at a press conference.
Both sides have made positive starts to their respective European campaigns this season, as Barca head into Tuesday's game with a 100 per cent record from their opening two matches, while the Hoops are similarly unbeaten, picking up four points.
However, the hosts' injury problems in defence mean the likes of Gerard Pique, Carles Puyol and Dani Alves will miss out, and Miku hopes their lack of options at the back will play into Celtic's hands.
"We have to take advantage of their weak defence. In strategic moves, they can be damaged," he added.
“They have injuries so that might give us a chance. The game will be seen around the world so that's maximum motivation [for us].
"I have won, lost and drawn to Barcelona so [I know that] this will be a difficult game. They are the best [team] in the world right now.
Rangers' demotion to the Scottish Third Division over the summer, as a result of financial irregularities, has heaped added pressure on Celtic to lift the SPL title.
But, the forward claims their domestic burden of expectation will serve them well on Tuesday, while highlighting the threat posed by Lionel Messi and his Blaugrana team-mates.
“If we don't win in the SPL, it would be terrible. So we will play this game with the same mentality," noted Miku.
“I have played against Lionel Messi many times and he is always thinking about the goal. It's possible to stop him though.
"But when you think about Barcelona, it's not just Messi. We have to be wary of all their players."