The Reds confirmed that the Cameroon defender will be joining the Anfield outfit at the end of the season on a free transfer after he opted not to renew his contract with the German club.
Liverpool have begun their summer transfer moves early as Jurgen Klopp looks to bolster his squad ahead of his first full season in charge at Anfield.
And former Liverpool star Aldridge was thrilled to see the Merseyside outfit get their summer transfer plans under way so early.
Writing in his column for the Liverpool Echo, Aldridge said: “The signing of Joel Matip has been confirmed, and I’m pleased to see the club already putting plans in place for next season.
“I won’t profess to be an expert on this lad, but he’s got good pedigree, decent experience and, I’m told, excellent aerial ability. And we all know how much we need that!
“Getting him in on a free represents excellent business. It helps fix a problem without taking a chunk out of our budget, which is a bonus.
“Hopefully he will prove to be a little gem of a signing.”
Liverpool returned to winning ways in the Premier League in style on Sunday afternoon with a thumping 6-0 win over basement club Aston Villa at Villa Park.
The Reds take on Manchester City in the League Cup final later this month.
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