Brazil’s Cesar Cielo added the men’s 50m freestyle gold to his sprint butterfly title at swimming's world championships on Saturday — just ten months after surgery on both knees.

Cielo, the defending champion and world-record holder, clocked 21.32secs with Russia’s Vladmimir Morozov taking silver at 0.15 seconds adrift and Trinidad and Tobago’s George Bovell 0.19 behind in third.

This was Cielo’s second gold of the week after winning Monday’s 50m butterfly final.

After winning bronze in the 50m freestyle final at the London Olympics, Cielo underwent surgery on both knees at the end of 2012 and has only been able to train properly since March

South Africa’s Chad le Clos also claimed his second gold, winning the 100m butterfly, but there was disappointment for birthday boy Ryan Lochte as he finished sixth.

The 21-year-old le Clos, the Olympic and world 200m champion, clocked 51.06sec with Hungary's Laszlo Cseh 0.39 seconds behind and Poland’s Konrad Czerniak 0.40 adrift.

le Clos has also won the 200m final on Monday.

There was disappointment for Lochte, who failed to add to the 15 world titles he has won in his career, but has a chance of a 16th gold in Sunday's 4x100 medley relay final after the morning’s heats.

“I felt really good in the water, but I couldn't get a medal,” said the USA star, whose haul is second only to Michael Phelps' total of 26 world titles.

“It's my first international 100m ’fly and I'm still learning how to swim it well. My goal is now is just to get ready for the medley relay on Sunday, I'll celebrate my birthday after that.”

Franklin gets her fifth

American Missy Franklin won her fifth gold at Barcelona bagging women’s 200m backstroke event, with Australia's Belinda Hocking second and Hilary Caldwell of Canada third.

The 18-year-old Franklin clocked 2mins 04.76sec in a new championship record with Hocking at 1.90secs back and Caldwell at 2.04 adrift.

“This is awesome. I'm exhausted,” said Franklin after her powerful performance, which was just 0.7sec off her world record.

World records

Katie Ledecky of USA broke the women’s 800m freestyle world record to win gold, with Denmark’s Lotte Friis second and New Zealand’s Lauren Boyle third.

The 16-year-old Ledecky, the 1500m freestyle world-record holder and world champion, clocked a new record for the 800m with 8min 13.86sec with Friis at 2.46sec back and Boyle at 4.72 adrift in a new Oceania record.

Lithuanian teenager Ruta Meilutyte claimed her second world record of the week when she beat Russian Yuliya Efimova’s previous best in the women’s 50m breaststroke.

Meilutyte, who swam faster than anyone before her in the semifinals of the 100m on Monday, clocked 29.48 seconds in her semifinal to beat Efimova’s mark of 29.78 set in qualifying earlier on Saturday.

The results: Men: 50m freestyle: 1. Cesar Cielo (Bra) 21.32s; 2. Vladmimir Morozov (Rus) 21.17; 3. George Bovell (T&T) 21.11. 100m butterfly: Chad le Clos (RSA) 51.06s; 2. Laszlo Cseh (Hun) 51.45; 3. Konrad Czerniak (Pol) 51.46.

Women: 800m freestyle: 1. Katie Ledecky (USA) 8.13.86s; 2. Lotte Friis (Den) 8.12.40; 3. Lauren Boyle (NZ) at 8.09.14. 200m backstroke: 1. Missy Franklin (USA) 2.04.76s; 2. Belinda Hocking (Aus) 2.03.86; 3. Hilary Caldwell (Can) 2.02.72. 50m Butterfly: 1. Jeanette Ottesen Gray (Den) 25.24, 2. Lu Ying (Chn) 25.42, 3. Ranomi Kromowidjojo (Ned) 25.53.

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