Alistair Brownlee beat younger brother Jonathan by two seconds to win Madrid's World Championship Series race.
A third successive victory in the Spanish capital for Alistair, 23, piled the pressure on title rival Javier Gomez, who finished 44 seconds behind.
It was the Yorkshire brothers' first time together on the podium.
They were so far ahead that Alistair could even wait to celebrate with his brother before crossing the finish line in one hour 51 minutes, seven seconds.
Alistair said: "It had to happen some time and why not have it happen in Madrid, a race where I have done really well and such a fantastic course."
Jonathan added: "It was really good, we train hard together and it's a bit strange because we've done it in small races but never in a world series.
"It's a bit of a strange feeling but really nice that he waited for me - it was really a special moment."
Gomez said: "The Brownlees were just on a different level on the run, so I couldn't do too much.
"I tried on the first lap, I tried to follow them but I know that was not my pace. I was waiting to see if they would slow down but they didn't, they went faster and they smashed me."
After a fast swim, 12 athletes broke away early on the bike and opened up a 90 second gap by the second transition before the Brownlees dominated the run.
The decisive moment came when Alistair broke away with two kilometres to go - a move that the rest of the field had no answer to.
Reigning Olympic champion Jan Frodeno was sixth with Britons Will Clarke and Stuart Hayes finishing 24th and 35th, respectively.
The win puts both Brownlees in poll position for the Olympic qualification races in London in August and Beijing in September.
The women's race takes place on Sunday and can be watched on the BBC Red Button and the BBC Sport website for UK users.