Two corporals in the British Royal Marines have struck out into the unforgiving North Pacific Ocean in a 7.9-meter rowing boat called Crackers this weekend, aiming to complete the 8,000 km crossing from Japan to California in a record 120 days.

Tim Welford, 32, and Dominic Mee, 31, will attempt to better the 133-day mark set by Frenchman Gerrard D'Arbaville in 1992 on the west-to-east route, and were confident that their training would pay off before they set off from Choshi, Chiba Prefecture, 110 km east of Tokyo.

"It's more mental preparation than the physical side, and the only way to be ready for ocean rowing is to go ocean rowing," said Welford.