Belgrade, March 21 : Reigning Olympic champion Armand Gustav Duplantis of Sweden broke his own pole vault world record for a second time to clinch a gold at the World Athletics Indoor Championships here at the Stark Arena. With a clearance of 6.20 meters on his third and final attempt on Sunday, the Swede bettered his own world record by one centimeter. The earlier record was set by him less than two weeks earlier. Duplantis cleared 6.19 at the Belgrade Indoor Meeting at the same venue on March 7. The silver medal went to Rio 2016 Olympic champion Thiago Braz of Brazil who cleared 5.95 meters. American vaulter Chris Nilsen, the Tokyo Olympic silver medallist, claimed the bronze with a clearance of 5.90 meters. BAV MR