He said that the club need a radical overhaul if they are to combat what he described as years of mismanagement, which yesterday resulted in their relegation to the Championship.
Although gracious in defeat after his side went down 1-0 at Aston Villa, Shearer revealed his shock at the extent of Newcastle's chronic problems and observed that there were "a million things wrong with the club". He also admitted that Newcastle had deserved to drop to the second tier of English football – for the first time in 16 years.
But he also blamed himself for Newcastle's demise. "The three worst teams deserved to go down and, unfortunately for me, Newcastle was one of them," Shearer said.
"Big changes need to be made at the club, players need to go in, players need to go out.
"I came in expecting to turn things around. I take my share of the blame. I thought I could get the right results for us."
"There are huge problems at the club, which are clear for everyone to see," he said. "It has not just gone on this season, but last season, the season before, and four seasons before that. The fact is that inside the dressing-room hasn't been good enough. I include myself. I include Joe [Kinnear], Chris [Hughton], Kevin [Keegan], Mike [Ashley]. Newcastle have got what they deserved."
Hull's 1-0 defeat at home to Manchester United meant Shearer's side only needed to equalise against Villa to avoid the drop, but Newcastle's players produced a supine performance.
On his future, Shearer said he had not been offered the manager's job for next season, adding he would hold talks with Ashley this week.
He added: "I don't think it would take a genius to work out what is wrong with the club. There needs to be an overhaul."