Liverpool must move quickly to replace Philippe Coutinho, former Reds striker John Aldridge has warned.
Coutinho headed to Barcelona last night after Liverpool accepted a British record bid, worth up to £142million, from the Catalan club.
The 25-year-old Brazil international, who arrived at Liverpool from Inter Milan for £8.5million in January 2013, scored 54 times for the Anfield side.
"I am not surprised but disappointed he [Coutinho] is leaving because he is a fantastic player to watch," the former Republic of Ireland player told BBC Radio 5 Live's Sportsweek programme.
"£140million is a lot of money and Liverpool have to spend it wisely.
"They have spent £75million of it wisely on Virgil van Dijk - a player we have needed for some time in a leader at the back - but he [Coutinho] needs replacing and we have got to do it ASAP."
Leicester's Riyad Mahrez - a key player for the Foxes when they won the Premier League back in 2016 - has been linked as a potential candidate to fill Coutinho's shoes.
Aldridge, who scored 63 times for Liverpool, believes the Algeria international must be considered.
"If you look at the way Coutinho plays, he [Mahrez] is very similar," Aldridge added. "He is older, he has played in the Premier League for some years and everybody has seen the ability he has got, so he ticks a lot of boxes.
"You need that type of player similar to Coutinho who sees that pass, can do something extraordinary outside the box, can bend it in the top corner and is good on free-kicks as well."