LAP the world challenger Sam Greatrex, from Halesowen, is set to complete his gruelling 3,500-mile row across the Atlantic Ocean on Friday in record-breaking time.

The cancer survivor, who hopes to make fastest human-powered circumnavigation of the Earth, and his four-strong team are due to reach Georgetown, Guyana, in just 53 days.

On Monday, he tweeted a quick update: "Hope to shout 'Land Ahoy!' in four days time. Thanks everyone for the support, it's a great help."

The 29-year-old, of Cloister Drive, is crossing the ocean in a 28ft purpose-built rowing boat with a cabin at each end and three rowing seats positioned in the centre.

His cherry-picked crew is made up of Dutch rower Ralph Tuijn, former England ladies tug-of-war champion Tara Adams, Nicholas Sen, a scientist and Ironman tri-athlete Nicholas Sen, from Essex, and globe-trotting adventurer Jim Alssord.

They set off from Lagos in Portugal on January 26 and look set to beat their own 70-day estimate to reach South America, rowing in shifts 24 hours a day.

The team hopes to clinch four Atlantic Ocean world records, including the fastest crossing from mainland Europe to mainland South America.

The specially-designed boat, which cost tens of thousands of pounds, is built of carbon for speed and self-rights if it capsizes.

The team are surviving on a diet of high-calorific freeze dried meals and treats including chocolate bars and salted peanuts.

Mr Greatrex, who was diagnosed with non-Hodgkin lymphoma when he was 10 years old, aims to smash 11 world records in his attempt to cycle and row 32,000 miles around the world in18 months and raise £240,000 for Macmillan Cancer Support.

He completed the first 2,000-mile European leg of his journey before Christmas after setting off on his bicycle from Paris on September 6.

Anyone wishing to make a donation to support his challenge can do as at justgiving.com/laptheworld