Sun, 21, added the world title to the Olympic crown he claimed a year ago, and just as he did in the London 2012 final, Yang dominated from early on in Barcelona.
The Chinese clocked 3min 41.59sec to claim the world title, finishing more than three seconds ahead of Hagino, who swam 3:44.82, while Jaeger finished in 3:44.85.
At the halfway stage, Sun was on track to break Paul Biedermann’s world record of 3:40.07, set four years ago at the Rome world championships, but the German ultimately holds on to the mark set using the now-banned high-tech suits.
After Sun finished second in the 400m freestyle at the Shanghai 2011 world championships, the 1500m freestyle world record-holder will be aiming to defend his 800m freestyle crown when the heats start tomorrow.
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