The USA and Japan renewed an 80-year-old rivalry as they both clocked 7:03.30 in the heats of the 4x200m freestyle to take lanes 4 and 5 for the final. No team other than the US, with its 6:58 world record, has ever gone faster. In the wash, 11 teams got inside 7:10. Two years ago in Melbourne: no team got inside 7:10 in heats. Japan's national record stood 6sec away, year-on-year. Look back to Melbourne and we see Japan's best male quartet on 7:13.68, 11th best in the world.