Newcastle struggled to break down Portsmouth in last night's goalless draw at St James' Park in a game Shearer had identified as key to their survival.
They now have just four games to save themselves and face a daunting trip to Anfield this weekend.
Close call: Mark Viduka (right) cries out in anguish after fluffing a chance against Portsmouth
'Confidence in football is a huge thing, winning football matches becomes a habit and losing football matches becomes a habit,' Shearer said.
'At the moment it's proving very difficult to get that elusive win. If we can get it then we'll go on a run, but it's proving very hard to win a football match.
'I think there will be three or four nervous teams come the last day of the season, we have to make sure we're still in there fighting and I believe we will be.
Head scratcher: Newcastle manager Alan Shearer (centre) and coach Iain Dowie (arms folded) look on during the 0-0 draw with Pompey
'We're disappointed not to get three points (against Portsmouth), I thought we've created enough chances to have won the game.'
Newcastle are three points adrift of safety, but with Hull and Sunderland themselves struggling Shearer believes the relegation places will be decided on the final day of the season.
'I don't know what's going to be enough to survive this season, I don't think anyone does the way this season's going.
'I think one thing's for sure, it will go right to the wire and I still believe there are going to be more twists and turns between now and the end of the season.'
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