The Magpies will face Chelsea on Saturday in Shearer’s first game in charge for the club.
Shearer said: “I keep hearing people say it is a tough game. I understand that.
“Chelsea have world-class players and a great, experienced manager. They are going for the Premier League and they are in the quarter-finals of the Champions League.
“However, I still think it is a great game for us to have. I’m not having the fact people keep saying, ‘we will not get anything here’.
“I do not accept that, I really don’t. If we do not gain anything tomorrow and the other teams win, they will be five points ahead of us.
“We do not want that. We have to take something.”