Talented Rehan Poncha stole the limelight, breaking his own junior national record in the 200 metres individual medley as Karnataka ruled the roost, pocketing 10 of the 16 gold medals decided, on the opening day of the Junior National aquatic championships in Delhi on Tuesday.

After a brief stoppage when heavy rains interrupted the proceedings at the Talkatora swimming pool, Poncha stopped the clock at 2 minutes 14.33 seconds to clip more than two seconds off his earlier mark of 2:16.69, set in the previous edition of the championships in Chennai last year.

The 16-year-old returned from Perth, Australia, only last week where he was on a training scholarship.

There was an air of expectancy as Poncha got on the starting blocks for the start of the 200 metres individual medley in the boys' group I.

At the end of the first 50 metres of the butterflystroke, Poncha, who clocked 28.94, was lying second, but he came back strongly, taking the lead in the backstroke to time 1:03.21 seconds at the 100 metres mark.

The 16-year-old college student from Bangalore timed 1:42.95 seconds at the 150 metres mark after the completion of the breaststroke and by this time he had established a big lead.

At the finish he was more than seven seconds ahead of second-placed Merwyn Chen of Delhi.

Chen clocked 2:21.81 seconds while Poncha's teammate M N Sidhartha came third in a time of 2:22.26.

Later Poncha said his priority is to do well in the World championships coming up in Barcelona, Spain, and also to qualify for the Athens Olympics.

"The stint in Australia greatly helped as the intensity is a lot more there. But I was not expecting such a good time. I am surprised," said Poncha, thanking the government, Swimming Federation of India and Sports Authority of India for sending him abroad.

The star in the girls' section was Karnataka's Ambica N S Iyengar, who won two golds in the group I category, in the 200 metres freestyle and 100 metres breaststroke.

Maharastra won three gold, Bengal two while Tamil Nadu opened their account when R Aishwarya won the last event of the day, the 50 metres backstroke in girls' group I.

The other gold medal winners were Karnataka's S Srinivas (200 metres freestyle - boys' group I), Rohith Hawaldar (200 metres freestyle boys' group II), Shubha C (200 metres freestyle girls' group II), P Arjun (100 metres breaststroke boys' group II), V Sivaranjini (200 metres individual medley girls' group I), Bharath Kumar V (200 metres individual medey boys' group II) and N A Sandeep (50 metres backstroke boys' group II).

The first to break Karnataka's total dominance was Bengal's Gairik Bardhan, when he beat B M Madhu Kumar to win the 100 metres backstroke in the boys' group I.

Bengal picked up another gold through Samir Das in the 50 metres backstroke boys' group I.

The pride of Maharashtra were gold winners Nimisha Gupta (100 metres breaststroke in the girls' group II), Jestine Mellocastro (200 metres individual medley girls' group II) and Komal Athare (50 metres backstroke girls' group I).