The 34-year-old Hungarian is leading Britain's defending champion and Olympic gold medallist Giles Scott by three points with two races left.

The overnight leader Alejandro Muscat, of Spain, has dropped to third, 12 points further back.

The two light wind races were won by Croatia’s Josip Olujić and Nicholas Heiner of The Netherlands on a grey day in the Polish city on the Baltic coast. 

With the seven to eight knots at the start dropping to three to four downwind, Olujić led at the first mark from Turkey’s Alican Kaynar, a winner twice yesterday. 

The pair managed to separate themselves from the fleet, with Olujić controlling the rest of the race to take the win from Kaynar as Spain’s Joan Cardona took third place.

The wind was starting to shift right again in race eight as Muscat reached the top mark first, just ahead of Heiner.

But Heiner then pulled away, winning the race by a huge margin. Croatia’s Milan Vujasinovic rounded the gate in second with Berecz finishing third.

This result coupled with a fourth-place finish in the previous race helped Berecz, who competed in laser class at London 2012 and Rio 2016, rise to the top of the standings.

After an impressive 2019 season, Heiner was widely expected to be a serious challenger in Gdynia.

But he has found life difficult in the conditions as he sits in seventh place, 31 points off the top.

"It’s not been the greatest of weeks for me," Heiner said.

"I’ve been unlucky in a few races and make quite a few stupid decisions but today was a bit better again and I won the last race.

"Definitely need to step it up a bit tomorrow for the final two races. It’s not the easiest place to sail, but that makes it fun.

"Of course with the calendar this year being overthrown with the pandemic it’s been quite hard to know what to really prepare for.

"Once it was clear we had the Europeans and the Worlds, we had a nice training group in Holland.

"We probably did a bit too much leading up this event as we were peaking for the Finn Gold Cup in Palma, but that got cancelled, so too short to switch around for the Europeans.

"But I think we did a lot of good training over the summer, and it’s been nice to do that at home."