Villa were thumped 6-0 by Liverpool on Sunday to leave them bottom of the Barclays Premier League and eight points from safety.
Mortimer captained Villa to European Cup triumph in 1982 and also became their first skipper for 71 years to lift the First Division trophy a year earlier.
Villa are plummeting towards the Sky Bet Championship and former midfielder Mortimer slammed the under-performing players.
"There is a Villa side out there who, for me, the effort is not there. The understanding around how to play as a team is not there," said Mortimer, who played more than 400 games for the club
"It could have been more. I never expected that, I expected maybe 2-0 but 6-0 was a shocking result.
"The manager has to get players to appreciate what this club is all about and get on that pitch and put performances in because that was shocking.
"Put the right manager in, a guy who understands what the Premier League is all about. Until they get that right they won't get the right players.
"I am disappointed for the fans, this has been coming over the last three seasons.
"Sooner or later it had to happen. Players have to accept that performance is not good enough."
And Mortimer insisted Villa should have appointed Nigel Pearson, instead of Remi Garde, when they sacked Tim Sherwood in October
"For me I always felt it should have been Nigel Pearson coming in. I think the ideal person who should have taken this job was Nigel Pearson," he said
"What he did last year to get (Leicester) up the league, and then they have gone on from there and are now top, it is unbelievable."
Source: PA