After WrestleMania , Lesnar turned his attention to John Cena , who had returned from injury in February 2003 and who had been F @-@ 5'd into a ringpost in the same manner Angle had been . Cena claimed Lesnar nearly ended his career and even named his new finishing move the " F.U. " as a jab at the new champion . The feud ended in a match at Backlash when Lesnar defeated Cena . On the following episode of SmackDown ! , Lesnar returned to his rivalry with Big Show after he injured Rey Mysterio badly during their match at Backlash . Show 's attack resulted in Mysterio being carried out on a stretcher and back board and Big Show took Mysterio off the stretcher and swung the back board into the ringpost , compounding the injury . Lesnar called out the Big Show , who demanded that Lesnar put his title on the line against him . This led to a stretcher match at Judgment Day for the title . Lesnar successfully retained his title with help from Rey Mysterio and a forklift . During the scripted rivalry , on SmackDown , Lesnar lifted Big Show off the top @-@ rope in a superplex which caused the ring to collapse on impact .