Ben Affleck won the top award at the Directors Guild of America on Saturday for the movie Argo.
It was his fourth this season. He was named as best director at both the Producers Guild and the Screen Actors Guild awards last weekend.
Affleck also won best director at the Golden Globes while Argo won best drama.
The Oscars will be held in Hollywood on 24 February, when Argo is one of the contenders for the best picture award.
But the Academy of Motion Pictures Arts and Sciences did not nominate Affleck for best director.
Since 1948, there have been only six occasions when the Directors Guild of America winner has not gone on to win the Oscar for best director.
"I have nothing but respect for the Academy," Affleck said on Saturday adding that he was thrilled the film was nominated for the Oscar for best picture.
"You are not entitled to win anything," he said.
Argo is an account of how a CIA agent extracted six American personnel from Iran after the US Embassy was stormed during the Revolution in 1979.
Affleck won an Academy Award and a Golden Globe Award for the screenplay for Good Will Hunting (1997), which he co-wrote with Matt Damon.