In anticipation of “Shark Week,” the Discovery Channel had been drumming up hype for a one-hour special that sought to answer a burning question: Could Olympic gold medal swimmer Michael Phelps outpace a great white shark in the open sea?

The answer was unveiled Sunday in ”Phelps vs. Shark: Great Gold vs. Great White.”

Note to self: Never challenge a great white to a race.

Phelps did not actually race a real shark for the show ― to the profound disappointment of many viewers ― but one thing was clear: 28 Olympic medals mean nothing when you’re competing against one of the fastest sharks on the planet.

For the 100-meter contest, which took place in the frigid waters off Mossel Bay in South Africa, Phelps wriggled into a 1-millimeter wetsuit and wore a mono-fin specially designed for the event.

As for his fishy rival, researchers developed a “cutting-edge water vehicle prototype” to record a great white’s speed along the same stretch of sea. A courageous guy then rode this vehicle ― with bait attached ― as a real great white raced behind him.

To prepare for the race, Phelps went to “shark school,” where he encountered a number of sharks, and even dived in a cage with some of them.

For the final “face-off” with the great white, however, Phelps swam the 100-meter stretch alone, and images of a great white were displayed alongside him using CGI.

“Clearly, we can’t put Michael in one lane and a shark in the far lane,” said Dr. Tristan Guttridge, a shark expert involved in the show. “We have to do simulation. We’ll use our speed data that we’ve [collected] in all our testing.”

Phelps clocked a time of 38.1 seconds, two seconds slower than the CGI shark.

“I don’t think that would probably end very well,” the swimmer told Vanity Fair in the days leading up to the show’s airing.

Still, “Shark Week” fans who were lured by Discovery’s purposefully ambiguous promotion of the show felt gutted when it became clear that Phelps wouldn’t be swimming alongside the real deal. They vented their frustrations on Twitter on Sunday.

When Michael Phelps said he was gonna race a shark this is how I pictured it happening #SharkWeek pic.twitter.com/GiEfJssNhL — Ryan Homler (@RHomler) July 24, 2017

Should've called it Michael Phelps vs a Computer Generated Simulation. Huge letdown @Discovery — Jimmy Kozeny (@jkoz19) July 24, 2017

am i the only one who thought they literally were gonna throw phelps in the ocean w a great white to see what would happen or #SharkWeek — alyssa smith (@lyskaye) July 24, 2017

Call me crazy but I thought they were gonna put Phelps up against a real shark not a simulation. I feel robbed. #SharkWeek #PhelpsVsShark pic.twitter.com/XgdEphkl6m — Meg Conley (@MegDownSouth) July 24, 2017

Michael Phelps has been hyping up that he's going to race a shark for months now. He did it tonight and it was a damn CGI shark #FakeNews — Cole Hill (@theSwoleCole) July 24, 2017

Reactions from the shark community after the Phelps/fake shark competition. pic.twitter.com/8vziyzWOjr — Mike Sciandra (@MikeSciandra) July 24, 2017

i spent 60 minutes of my life watching a build up to michael phelps race a fake computer generated shark. i'm pissed — spo (@spoyourboat) July 24, 2017

The real winner of Phelps Vs Shark was anyone who didn't waste an hour of their life. #SharkWeek — Jack Scott (@Jacked_Scott) July 24, 2017