The hosts are aiming to reach the last four of the tournament for the first time but face a difficult task against the three-times Asian Champions who ruthlessly dispatched Saudi Arabia 5-0 in their final group game on Monday.
"We are preparing ourselves to meet one of the best teams in Asia," the French coach told reporters before Friday's match at the Al Gharafa Stadium.
"Looking at their match against Saudi Arabia, you could call them the Barcelona of Asia. We can't compare what happened against the Saudis to our match though as they had already been eliminated.
"They're well organised and disciplined. Sometimes you feel like you'd need a computer to beat Japan."
Barcelona's passing and pressing tactics have drawn widespread admiration and Metsu may have been overly kind to Japan by comparing the two teams but the Blue Samurai have certainly improved after their opening draw with Jordan.
"We took our chances in the match (against Saudi Arabia) and at the same time, our opponents attacked us, so they left space for us," Japan coach Alberto Zaccheroni said.
"Secondly, we sped up our performance, and the content of our performances is getting better and better.
"I hope we play even better than in our three previous matches against Qatar. We can't just evaluate ourselves based on the match against the Saudis. We just need to focus on Qatar."
Friday's second quarter-final between Uzbekistan and Jordan at the Khalifa Stadium offers the victors the opportunity to reach the Asian Cup semi-finals for the first time.
"We have reached this quarter final and we deserved that on merit as we played very well. We are facing a very strong team in Uzbekistan and we are very confident. I have confidence and trust in my players," he said.
"Jordan is a good dangerous team, a very lucky team that can play football," he said.
"(I'm a) bit afraid because sometimes there is no chance (for them) to score but they score, maybe somebody help them from upstairs."
