Jorge Lorenzo's hopes of becoming the first Yamaha rider to win the opening two races since Wayne Rainey in 1990 were extinguished after just five laps in Argentina.
The Qatar victor had qualified in third and got the holeshot at the start - but dropped swiftly to sixth, the position he fell from after losing the front of his Movistar Yamaha at Turn 1.
“I cannot be happy. Conditions were not perfect, but it was the same for everyone,” Lorenzo said. “Half of the riders more-or-less crashed and the other half stayed on the bike. It was not easy. I didn't know how to ride the same as the first riders and, not only that, I also didn't have the patience to stay on the bike.
“So just forgot this race and try to be positive because normally we race in dry conditions and in dry conditions we are competitive, and also in completely wet we are competitive. In life and racing sometimes you have a bad day, but you cannot forget all the good days that you've had.”
The Spaniard explained that a lack of focus led to him going off-line slightly at turn one, sending him into the path of a damp patch.
“A difficult corner because there was just a tight line that was completely dry. The other lines had a lot of damp patches, so if you enter a little too fast or too wide it was difficult to stay on the bike,” he said. “Unfortunately I made a mistake. Normally in dry or with full wet I'm very focussed, very concentrate. But today I wasn't riding very well, or focussed for these particular conditions.”
Why weren't you as focussed?
“Because I wasn't competitive. Because the patches were there and didn't dry up. And I wasn't competitive enough to be as fast as the other riders. They stayed on the bike and I didn't.”
The DNF means Lorenzo has slipped to fourth in the world championship, 16 points from race winner Marc Marquez.
Lorenzo's team-mate Valentino Rossi finished second.
By Peter McLaren