The former England striker is dismayed the Magpies let the forward leave without recruiting a new front man after 22-year-old Carroll made a record-breaking Ã‚Â£35m switch to Liverpool late on transfer deadline day.
Newcastle boss Alan Pardew has admitted he made a number of unsuccessful last-ditch bids for some players on Monday night, including Charles N’Zogbia.
“I’m staggered just like the rest of Newcastle fans,” Shearer told BBC Five Live: “I am surprised at how quickly it came along and it’s an astonishing amount for a young guy with huge potential.
“It’s all right selling your best player, but not getting anyone in to replace him is staggering. People are saying that Liverpool have sold Torres, but they have got two guys in for over Ã‚Â£50m to replace him. I just hope Newcastle invest some of the Ã‚Â£35m in new players at the end of the season.Ã¢â‚¬Â
He added: “I am disappointed as he is Newcastle’s best player and their best hope of being successful this season and getting a Europe League place. They would have just been happy to avoid relegation at the start of the season but, mainly because of him, they had a chance of a Europa spot.Ã¢â‚¬Â
Shearer believes Carroll with develop into a top player under the stewardship of Liverpool boss Kenny Dalglish. The former Blackburn manager brought Shearer to Ewood Park from Southampton for Ã‚Â£3.6m in 1992 and the England international went on to score 112 goals in 138 games under the Scottish boss before joining Newcastle for Ã‚Â£15m in 1996.
“He is a huge loss, he has carried Newcastle at times this season. There are not many players like him,” said Shearer. “He is big, strong, very good in the air and has a good left foot. You get that ball in the box and there aren’t many that could stop him, but he will be a tremendous asset to Liverpool.
“Having worked with Kenny Dalglish I can tell you he is not only a great man, but a great manager. If anyone can get the best out of him then Kenny will.Ã¢â‚¬Â
He added: “To work with one of the greatest football figures of the last two decades, I know he will learn the tricks of the trade from him and improve.”
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