A comprehensive win puts the Czechs in the driving seat ahead of their second leg trip to Serbia.
Red Star began the match with their new coveted goal-machine Dejan Lekic playing as the lone striker. However, head coach Vladimir Petrovic may have acted hastily in his tactical decision, as playing so deep invited the hosts to come forward and attack.
It didn't take long for the Sesivani to capitalize on their opponents lying so far back, as Zdenek Senkerik found the net midway through the first half to give the home side a 1-0 lead.
Red Star quickly began looking dejected, as their long balls up to Lekic were proving an exercise in futility - the visitors struggling to get a touch of the ball in the midfield area.
Slavko Perovic was sent out at half time in place of midfielder Nenad Sreckovic in the hopes that another forward could add the cutting edge that the visitors so badly needed.
Again though, possession in the middle of the pitch was hard to come by for Red Star, even with Perovic dropping back to look for the ball himself.
Slavia skipper Jaroslav Cerny proved to be a handful throughout the duration of the match, providing limitless chances as he bombed down the left flank.
Senkerik made it two after 65 minutes, nodding in a perfectly timed cross from the dangerous left foot of Cerny. Red Star were quickly losing interest as their heads dropped.
The icing on the cake came with minutes to go, as a clever back-heel from Stanislav Vlcek played in Cerny for what looked sure to be goal number three.
The captain's shot was well saved by Bojan Pavlovic, but the resulting rebound fell right to the feet of Vlcek who made no mistake in bringing the scoreline to three.
Belgrade will have to dig deep if they are to turn things around in Serbia, but judging by the form of the Czechs tonight, it looks doubtful that we will see Red Star feature in the Europa League after the return leg.
Stephen Crawford, Goal.com
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