If John Moraga ‘s goal is to cut off the cage and force the fleet-footed Demetrious Johnson to fight, he’ll need to add speed to his power in order to make that happen. Of those two oft-spoken qualities that divide opponents, UFC flyweight champ Johnson (17-2-1 MMA, 5-1-1 UFC) possesses the edge in ability to strike, retreat and switch directions, which leaves title challenger Morgaga (13-1 MMA, 2-0 UFC) with the task of catching his foe at UFC on FOX 8, which takes place Saturday at Seattle’s KeyArena. The event’s main card airs live on FOX (8 p.m. ET/5 p.m. PT) following prelims on FX (5 p.m. ET) and Facebook (4 p.m. ET).