The Audit Bureau of Circulation (ABC) figures showed a sharp drop in sales for The Observer one month into its launch as a Berliner, while The Guardian's sales continued to fall.
McCall emphasised, however, that both the Guardian and Observer had delivered year-on-year increases of 5.9% and 3.05% respectively.
"In a market filled with free giveaways the figures show a performance of sustained success," said McCall.
However, the real losers were the Sunday tabloids. Overall, sales were down 4.9%. Richard Desmond's Daily Star suffered the biggest monthly percentage fall of 11.9%.
The Independent and the Daily Mail were the only non-Sundays to report a month-on-month rise, at 3% and 2.1% respectively.
