Tamberi, who famously shared the Olympic title with three-time world champion Mutaz Barshim of Qatar, cleared a world-leading 2.36 metres for gold. He missed at one attempt at 2.40 and then called it a night, his victory secured.
“I feel like a human being who beats superheroes,” Tamberi said.
The 31-year-old Tamberi, wearing one green sock and one red, and his face shaved on only one side, leapt into the water hazard of the steeplechase in wild celebration with Soufiane El Bakkali of Morocco, who had just raced to gold in the men’s 3,000m steeplechase.
“It’s crazy, it’s an indescribable feeling,” Tamberi said. “I have been rewarded for all the sacrifices made.
“I managed to stay focused, expressing my feelings. My secret is being myself on the platform. It worked,” he added.
The 24-year-old Harrison also cleared 2.36 but had more misses on the countback, and so took silver for his first senior global medal.
“I think this was the best year of my career,” Harrison said. “I was consistent in every competition. After qualification I was about to have fun in the final and enjoy the jumps.
“It is fantastic that I beat one of the Olympic winners and I equalled the other. This is what I came for. This result gives me a great confidence for the Olympic Games in Paris.”
Barshim cleared 2.33 for bronze, missing at all three attempts at 2.36. The 32-year-old, who has the second best jump in history – 2.43 behind Cuban great Javier Sotomayor (2.45 in 1993) – looked in for a rough night when he missed his first attempt at 2.25.
“Everything was different today,” Barshim said. “I came here with three world golds and one silver and managed to add a bronze tonight. Look at my career. If it was not me that did this, but someone else, I would like to be that someone. I am the only high jumper with such a medal count. This almost brings tears to my eyes.
“The rivalry between all the jumpers was incredible. I am happy that Tamberi won the gold,” he added. “It was a medal he was missing from his CV and he added it tonight. The Paris Olympics is my next goal but it will be my last. It will be more like a contest, not revenge.”
Elsewhere in Budapest’s National Athletics Centre, Olympic gold medallist El Bakkali claimed his second consecutive world 3,000 metres steeplechase title.
The 27-year-old held off world record holder and Olympic silver medallist Lamecha Girma of Ethiopia to win in eight minutes 3.53 seconds.
The 22-year-old Girma, who blazed to 7:52.11 at the Paris Diamond League on June 9 to break the 19-year-old world record, lost contact with El Bakkali over the final water jump en route to his third world silver in 8:05.44.
Kenyan Abraham Kibiwot clipped a barrier and fell heading into the final lap but scrambled back to his feet and then overtook team mate Leonard Kipkemoi Bett to take a well-earned bronze in 8:11.98.