The Czech minnows have arrived in Manchester ahead of what appears a daunting task at the Etihad Stadium.
City have scored 18 goals in their last three home games and will be confident of adding more against Plzen, who are yet to register a point in Group D.
But Vrba believes his side have learned from their 5-0 defeat at the hands of reigning champions Bayern Munich last month and will be a tougher proposition for City.
He said: "We have watched highlights of their games and can see they're a very strong team.
"They've got a busy schedule though, so we're hoping they might not play their strongest side.
"Any game from now on is huge experience for us and we'll be aiming to give them something of a hard time.
"Bayern was quite an experience and I agree with the reporters' views, we didn't play very well.
"The quality of their team, their ability, the situation was all daunting for us, but I think we can draw on that and won't be as overwhelmed."
The pressure is off for City, having already qualified for the last 16, but they still have top spot in the group to aim for.
They will enter the game in good heart after hammering Tottenham 6-0 in the Barclays Premier League on Sunday.
Vrba said: "This doesn't surprise me, as they are very strong team.
"And they're clearly still not happy, as they also want to buy (Lionel) Messi, so they must want to get even better going forward!"
Vrba's comment about Messi was delivered tongue in cheek, with a recent interview given by City's Pablo Zabaleta - an international team-mate of the Barcelona superstar - having gained a life of its own on the internet.
He joked: "Czech reporters know everything! That's what's on the net over in the Czech Republic."
Plzen have conceded 12 goals in their four games but goalkeeper Matus Kozacik is also not worried about the prospect of facing City.
He said: "On one hand it's daunting, but on the other hand we're in the Champions League on merit so have to do our best.
"We just have to try and stop them scoring as freely as they did at the weekend and try and get some goals of our own too."