American extreme surfer Garrett McNamara has reportedly beaten his 2011 record for the largest wave surfed (unlimited) after riding a claimed peak of 100ft yesterday.

The potentially historic moment, which was captured on video in the clip below, took place in Nazaré off the coast of Portugal on a wave formed above an underwater canyon famous for being the world's biggest wave generator.

The canyon had previously been the scene for McNamara's triumphant record-breaking ride in November 2011, which saw him negotiate a wave which measured 23.77 m (78 feet) from trough to crest.

Guinness World Records is currently awaiting further evidence in order to verify if Garrett has indeed beaten his previous benchmark.

Garrett, a professional big wave surfer for the Body Glove International team, is part of an elite group that travels the world chasing storms and tracking swells in an effort to surf the largest waves.

In the past he has ridden breaks such as Waimea in Oahu, Mavericks in California and Todos Santos in Mexico.

Describing his latest daredevil feat, Garrett, 45, told ABC News: "You are just going so fast, it's really, really similar to snowboarding on giant mountains".

"And you're just chattering, flying down this bumpy, bumpy mountain. Your brain is getting rattled. Your whole body is getting rattled."

The record for largest wave surfed (paddle-in) remains held by Shane Dorian, who managed to successfully ride a wave measured at measured 57ft (17.4 m) in height without a tow at a break known as 'Jaws' off the coast of Maui, Hawaii, USA in March last year.

To learn more about Garrett and his other missions visit