Complex sentence: On the pre-show of the gathering, Zbyszko announced if Jarrett pinned Raven during the contest then he would earn a future NWA World Heavyweight Championship match, however, if Raven pinned Jarrett then Jarrett would not garner one for an entire year.
Split into simpler sentences: On the pre-show of the gathering, Zbyszko announced if Jarrett pinned Raven during the contest then he would earn a future NWA World Heavyweight Championship match. However, he added that if Raven pinned Jarrett during the contest then Jarrett would not have another title match for an entire year.