Red Star Belgrade travel poorly but they have an incredibly passionate, intimidating atmosphere at their home stadia. They are not to be underestimated in Belgrade.
Yes, passionate fans are a great addition, but they cannot win you the match. Serbian football is in a downfall for a long time, so I kind of ignored Red Star and thought they will get hammered.
I am pleasantly surprised by Red Star (back to back years in CL groups) so I plan to watch a game or 2 to see what that team is about and if they actually have some good players there.
While their national team is in not looking good for years now despite having very good players, their clubs are performing best since 1991 as Partizan is also playing good, and Serbia might have 2 clubs soon in Champions League.
In my opinion, their most important player is Marko Marin, easily, it was an excellent buy last year.