Lucho Gonzalez's 55th-minute goal proved to be the difference in the Group G encounter, with Paulo Fonseca's side holding on despite some late Vienna pressure.
And afterwards, Fernando admitted that the other sides in the group, Atletico Madrid and Zenit St Petersburg, may struggle to take points from their visits to the Austrian capital.
"It is very difficult to play in the Champions League," he said.
"They are very aggressive but we managed the most important, victory. All the other teams will also feel the same difficulties as we did, but I don't know if they (Vienna) will lose many points here."
The midfielder went on to insist that his side would be concentrating solely on their own results as the group stage progresses.
"We don't care about the other teams' results," he said.
"We only have to do our job and win our matches. Then we will see.
"It is always important to win away matches."
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