Rome, July 26 (DPA) South Korean defending champion Park Taehwan Sunday failed to make it to the finals of the 400 metres freestyle at the world championships, while the first championship record of the meet belonged to Swedish teenager Sarah Sjostrom.

Sunday saw the first day of competition in the swimming section of the world championships, which are being held in Rome from July 17 to Aug 2.

In the biggest upset of the morning, Park, who also took the gold medal at the Beijing Olympics last year, finished in a time of 3 minutes 46.04 seconds, placing him 12th - far off the pace of the eight-fastest swimmers who made the final.

The fastest time in the heats was registered by German Paul Biedermann, who swam a time of 3:43.01, setting a new European record.

The first championship record of the meet belonged to 15-year-old Swedish sensation Sjostrom in the ninth heat of the first event, when she swam a 56.