And just for good measure, the women’s squad, who had Megan Chapple playing a starring role, made it a terrific Sarnian double in the sunshine on Eastern Beach with victory in the team event.
By that time, they were being cheered home by the men’s champion who had won the earlier-starting race by pulling away from Jersey star Ollie Turner on the run leg after the two had been virtually inseparable on the cycle.
‘I hoped to podium,’ said Lewis, who took the winning tape in 2hrs 3min. 51sec.
‘I knew I would be up there because I looked at the field and I knew some of my closest rivals, so I definitely hoped to be up there in the top three and to get gold is just a massive relief and I’m so happy and proud.’
Turner had exited the water first with Lewis 20sec. behind but the rest of the field were already trailing so all eyes focused on the front two.
‘The swim was a bit of a struggle, I couldn’t see the buoys, so I went wrong a couple of times,’ admitted Lewis.
‘Luckily on the second buoy Ollie followed me the wrong way so he didn’t gain an advantage there, but the other time I thought I was going the right way and he was actually going the right way, because I spotted a different yellow buoy.
‘After that, everything went to plan.
‘After the swim I managed to chase Ollie down, we had a great little battle on the cycle and then it came down to the run and I think I just had a little bit more left at the end of the day.
‘It was an honest course and it was what I’d call a pure race.’
Led by Lewis, the Guernsey men’s team picked up team silver behind Jersey, with James Travers in seventh and Dan Galpin, 15th, the other two counters.
Chapple excelled in storming to a brilliant silver behind the outstanding gold medallist Susanna Sorensen of the Faroes.
Chapple and Guernsey teammate Amy Critchlow virtually exited the water together inside the top five, with the youngster then pushing on in the cycle leg to establish herself in a comfortable second spot with Sorensen out in front.
The gap remained fairly constant on the run, with Chapple crossing the line in 2-32-56, 89 seconds behind the winner but more than four minutes ahead of bronze medallist Lynsey Elliott of the Isle of Man.
Meanwhile, behind them Critchlow struggled badly with cramp on the run, but managed to find some rhythm again over the last lap or so to take fourth place in 2-38-28.
Chantal Green also produced a strong performance to come home 12th and crucially her time of 2-46-00 secured Guernsey the team gold by just under three minutes ahead of Jersey.
‘I’m so proud of them all. We have done so much training together that I know how much it means to all the girls and all the guys. It’s just amazing,’ said Chapple, who added that she was ‘overwhelmed’ by taking individual silver.
More in Monday's Guernsey Press.