A shark was spotted about halfway through the race from Narooma to Bermagui, swimming near the sweep of one of the rowing boats.

However, it quickly disappeared and the crew was able to resume changeovers soon after.

A strong northerly wind helped competitors along in the fourth leg of the 2013/14 Navy George Bass Surf Marathon.

However, the cooler winds resulted in two women competitors needing urgent medical assistance when they arrived at their destination.

The 24km leg from Narooma to Bermagui was just as exhausting as the other legs of the longest, toughest surf marathon in the world.

However, many competitors described it as much more “fun” than travelling into a head wind, which is what the conditions are expected to be on Thursday.

After notching up their first ever George Bass Marathon victory on Tuesday, the Tathra women’s veteran crew found the going tougher on day four.

Tathra finished in fourth place as the Broulee Bats secured the win.

The Tathra men’s veteran team finished in third place, while Bermagui’s mixed crew crossed the line in sixth spot in that race.

Thursday’s leg is the longest of all seven days at 36km, occurring just when competitors are physically and mentally drained.