Finishing fifth in the Laser 4.7 race, reigning world junior champion Onvlee is now within reach of his second successive title triumph in the world's largest junior sailing festival, although the UAE's Adel KHALID has not given up the chase.
Khalid took second place behind race winner Rolph OUDSHOORN from the Netherlands to continue his climb up the overall standings into third position, and he will be hoping to increase the pressure on Onvlee in the final three races.
Alkstedt could only manage eighth place in the day's single Optimist race, but it was good enough to keep her in the overall lead from team-mate Carl STROMBECK, the winner on the day from Denmark's Jes Lyhne BONDE and Adam JOHANSSON, son of the Swedish coach.
'Winds were very light and variable, and in the end we just could not set a course,' said Laser 4.7 race officer Tony LOCKETT of Britain, who was the principle race officer for sailing events at the Athens Olympics.
'In the first race they didn't reach the windward mark in the time limit so the race was abandoned. The course was then shortened, but when we re-started the race a third of the field didn't finish within the time limit.'
Looking forward to a big climax in the sixth edition of the Dubai Junior Regatta, Saeed HAREB, managing director of Dubai International Marine Club and the event's chief executive, said: 'We have had some wonderful racing to date, and with so much still at stake we're now looking forward to a very exciting final day.'
'There's a lot of talent on show here, and it's clear that we're watching some of the world champions and Olympic champions, and leading America's Cup yachtsmen, of the future.'
After the start of the Al Boom Marine-sponsored fourth race day had been delayed Outshoorn took control of the only surviving Laser race to win from Khalid, with Bahrain's Mohanna Al DOSARI taking a fine third place ahead of Pelt and Onvlee.
Another of the leading young Gulf nationals, Qatar's Hassan Al TAMIMI, was placed fifth in the Optimists race to finish the day in the overall top ten.