The Spanish champions slumped to their second La Liga defeat of the campaign in a 1-0 reverse at Sevilla on Saturday, prompting sharp words from Mourinho who questioned the attitude and commitment of a large number of his players.
"It's rare that after four games the boss has been so tough and the team have not raised themselves," Ramos told reporters, referring to earlier comments the Portuguese coach had made about his team.
"The moment has arrived for us to look at ourselves and say we can give more, that we should improve and change our attitude."
Real have taken only four points from their opening four games and are now eight adrift of arch-rivals and leaders Barcelona, who have a 100 percent record so far.
Although it is early days, Real lost only two games and drew four on their way to winning the title last season.
Daily El Pais headlined their match report on Sunday: "Madrid in a state of alarm," while sports daily As made reference to Cristiano Ronaldo's remarks from two weeks ago that he was sad.
Real's leading striker appears to have unsettled the side with his public outburst, prompting wide-ranging media speculation over the reasons for his unhappiness that the club have failed to staunch.
"It isn't a matter of whether Cristiano is sad or not anymore," As wrote. "Now all of Madrid is sad. Unexpectedly sad."
Real host Manchester City in their opening Champions League group game on Tuesday.
