The long-awaited new album by Adele, 25, looks set to break the modern record for first week sales.
Billboard, the music industry journal that publishes weekly charts, said the offering, released on Friday, appeared likely to sell at least 2.5 million copies in the United States.
No Strings Attached by boy band N'SYNC, starring Justin Timberlake, is the only other album which opened with sales above two million since systematic weekly tracking began in 1991.
No Strings Attached sold 2.4 million copies in its first week in 2000 - a year before the launch of Apple's iTunes, which drastically changed buying habits.
In a rare move that surely boosted sales, Adele's label chose not to make 25 available through streaming, a vast-growing platform that offers unlimited, on-demand music online.