Honda rider Dani Pedrosa has apologised to Ducati's Andrea Dovizioso for the clash that ended both of their Austin MotoGP races.
Pedrosa was running in fourth place behind Dovizioso on lap six when he lost the front end of his RC213V under braking.
The Spaniard fell off the bike, which then collected an unsighted Dovizioso as the Italian turned into the corner.
It ended Dovizioso's race on the spot, while Pedrosa rejoined and continued for five more laps before retiring.
"Unfortunately, I made a small mistake, losing the front end under braking when I was still turning into the corner," Pedrosa said.
"I lost control and tried to save the crash, but I ended up going down and taking Dovizioso with me.
"It's a shame to have finished the race in that way, and I feel especially bad for Andrea and want to apologise to him.
"I'm glad he's fine."
Pedrosa started the race eighth, having qualified 1.191 seconds behind team-mate and polesitter Marc Marquez, but was the only Honda, Yamaha or Ducati rider to pick Michelin's soft rear tyre for the race.
With that he felt more comfortable, and able to challenge for the podium before the incident.
"The practice sessions didn't go entirely well, but I approached the race with hope and I think we started quite well," he said.
"I gained positions and was in a very good group, and I think we could have fought with [Jorge] Lorenzo for second place; the pace we had was much better than in practice."
Dovizioso started the season with second place in Qatar, but leaves the Americas seventh in the points, having been collected in Argentina and Austin while running in a podium position.
"I think I'm very lucky because the bike is very heavy," he said.
"It can be worse. I have some pain but nothing really bad.
"It's very bad, what happened, because we could fight for the podium."
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