India’s teenage sensation Rehan Poncha today disappointed with a miserable performance in the World Swimming Championship where he finished 50th in the 400m freestyle event of the competition at Barcelona.Sixteen-year-old Poncha, who had created quite a splash in the pool in the junior nationals held here last month by winning four gold medals and setting new records, clocked 4 min 14.22 sec today to finish ahead of just eight swimmers in a field of 60, according to information received here. He finished almost 30 seconds behind Australian champion swimmer Ian Thorpe who was first in the qualifiers with a timing of 3:47.44.Richa Mishra fared no better in the women’s 100m butterfly event, though she did come close to the Olympic qualifying mark. Richa finished 40th in the 100m butterfly qualifiers with a time of 1:06.08 which was about two seconds off the Olympic qualifying mark. Karnataka girl Ambica finished seven places behind Richa with a time of 1:09.63 in the same event. In the 4x100m freestyle relay for men, India finished 17th.