The 25-year-old former racer broke the previous record by more than two hours on Sunday, finishing the 226.3km (140.6 mile) course in Kona, Hawaii, in 14 hours 23 minutes 56 seconds.
Monger stated he "wouldn't have dreamed in a million years" that he could surpass the record by such a large margin after finishing the 3.8 km swim in 17:29, the 180 km cycle in 7:26:50, and the marathon run in 5:26:26.
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