Australia’s dynamic sailing duo, Liesl Tesch and Dan Fitzgibbon, have sounded an ominous warning to their competitors in the Rio Paralympic regatta, surging to an early lead in their title defence on day one at Marina da Gloria.

The London SKUD18 gold medallists navigated strong tides to finish first in the opening race and second in race two, placing them in first position overall, three points ahead of Canada and Poland.

“We had a good first day. We’re happy to get that one out of the way,” Fitzgibbon said. “I think it’s going to be a tough week, so we just have to be prepared for that. There’s a lot to think about out there, so you’ve got to keep your head together.”

Fitzgibbon and Tesch made an immediate impact in eight to 12 knot winds, leading at every mark in race one and finishing 45 seconds ahead of second-placed Italy. In a close second race, they finished four seconds behind Canada.

Tesch praised her partner’s focus and determination, saying they were committed to making every post a winner.

“There’s five more days of opportunities to do the best we can on a very very tough race course,” Tesch said.

“It’s finally exciting to be out there racing another fleet on a proper racetrack. We’ve done a fair bit of training here, so to actually line up against the other boats is what we’ve come here to do – and they were as tough as we expected them to be. I think we’ve come off really well out of today but there’s another five days ahead.”

In the 2.4metre keelboat class, Matt Bugg produced a solid third and fifth in his opening two races, placing him fourth overall.

“The first day for me is always a little bit of a stress, making sure the boat is fine and just getting into a rhythm and worrying about nothing but racing on the course,” Bugg said.

Asked how he felt he sailed in the challenging conditions, he said: “Not to the best of my ability, but certainly not my worst either. I’m happy to end up with eight points after the first day because both those races were keepers. I’m pretty happy with that.

“The top mark was close up under Sugarloaf, which made the wind shifty, moving from side to side a lot and moving up and down in pressure. It was tough but we all had to deal with the same stuff. Some dealt with it better than me and I’ll try and make sure that that doesn’t happen again tomorrow.”

Bugg said the secret for the Australians will be to persist to till the end of the six day competition.

“It’s a cliche but you just never give up,” he said. “I’ve had regattas where I been seventh on the last day and ended up second. It gives you plenty of time to get back into it. Also plenty of time to knock yourself out of it, too, if you don’t sail well. But I’m pretty confident. I know I didn’t sail to my best today and I still had two keepers. I think the rest will be OK.”

In the three-person Sonar class, the Australian crew survived a protest which was resolved some six hours after the action on the water had finished.

Skipper Colin Harrison, a veteran of three previous Games, said their top position was earned through a combination of boat speed and sound strategy across the two races, in which they finished first and second to lead the fleet by six points.

“It was all good today, but we’ve got a lot of top competitors in our fleet, eight to 10 boats that are consistently up in the top three,” Harrison said.

“Whichever three sail best in this regatta are going to get on the podium. But it’s going to be close. It always is.”