Nintendo of America boss Reggie Fils-Aime has confirmed to USA today that 3DS sold less than 400,000 units in its first seven days on sale in the US.
The exec was speaking after the release of March NPD figures last night, in which it was all but confirmed by the tracker that the machine had sold in the 400,000 region last month.
DS sold 500,000 units in its launch week in America in November 2004.
Reggie shrugged off the failure to beat the DS number, though, describing the two launches as "apples and oranges".
"When we launched DS we launched going right into the Thanksgiving week," he said. "From a pure timing seasonality, you are not going to be able to compare the two launches."
He added: "We are going to be continuing to sell DS and that platform is going to continue to build on its legacy of the best-selling hardware system ever in the US. I would love to have the Nintendo 3DS eclipse that, but this is a new platform that we have just given birth to.
"I would love to have ongoing comparisons to the DS business because that would certainly mean we are doing a good job growing the Nintendo 3DS business."
3DS sold 400,000 units in its opening week in Japan, but had only sold just over half its initial stock allocation six weeks later.
The handheld beat DS's launch weekend sales figures in the US, selling 113,000 units in 24 hours.