The Italian powered down the white water course at the London Olympics to secure the gold at the men's kayak slalom Wednesday — on his 28th birthday.
Molmenti finished 1.35 seconds ahead of Vavrinec Hradilek of the Czech Republic, who gave his country its first medal of these Games.
Though Molmenti turned a year older, he proved he's certainly not too old as he bested two of the sports brightest young stars in the 25-year-old Hradilek and 23-year-old German Hannes Aigner, who won bronze.
"I finished my job. I'm so excited I've lost my voice," Molmenti said.
Hradilek set the tone with a fast early run that few in the field seemed able to match. But Molmenti was ahead of Hradilek's pace much of the way and crossed in 93.43 seconds.
Hradilek was just eighth in the semifinals but put down a clean run through the rough currents of the Lee Valley White Water Centre.
Hradilek had the crowd gasping afterward — but not Molmenti.
"I was not very stressed at the start and I was sure that if I just did my job no one could beat me," said Molmenti, who added an Olympic gold to his 2010 world championship and trio of European titles.
Slovenia's Peter Kauzer qualified with the best time for the finals. But the pre-race favourite had a rather sloppy final run and settled for sixth — more than seven seconds behind Molmenti.
Poland's Mateusz Polaczyk was fourth, just 1.22 seconds behind Molmenti.
New Zealand kayaker Mike Dawson failed to qualify for the finals after being penalized 100 seconds for missing two gates.
This time, Dawson's mother had nothing to do with it.
Kay Dawson, a judge for the event, penalized her son two seconds for hitting a gate on Sunday. Mike Dawson still qualified for the semifinals, but he missed a wave toward the end of his run and failed to go through two consecutive gates.
Each miss cost him 50 seconds, putting Dawson in last place and out of the 10-man final. But Kay Dawson was stationed at an earlier gate, which Mike passed through without any issues.
"It's a sport with so many variables. It's real easy to make mistakes, especially when you're racing semifinals and you're pushing everything to get one of those elusive 10 spots which fill up pretty fast," Dawson said. "There's no holding back and trying to play it safe."