Richardson said Coutinho "now fears his dream Camp Nou move is scuppered" as the Catalans' attention has moved on to Mane.
Per Daniel Zeqiri in the Telegraph, Liverpool resisted Barca's aggressive pursuit of playmaker Coutinho during the summer transfer window, reportedly rejecting a £138 million bid for the Brazil international.
Speaking to ESPN Brasil (via Glenn Price of ESPN FC), Coutinho said he was interested in a move to the Catalan giants but insisted he remains committed to Liverpool despite the Merseyside club blocking his switch:
"I received a job offer, like in life whatever work you do. Sometimes you're interested and sometimes you're not. In this case, like you all know, I was interested. My family too.
"But it's like I always said... it's a great honour to receive an offer for a great club like that. But it's also a great honour to be here. Liverpool is a great club. I'm here and I'm going to give it my best as always."
Having managed to keep Barca from snapping up Coutinho, Liverpool may be faced with another challenge to keep hold of Mane.
The 25-year-old Senegal international moved to Anfield from Southampton in the summer of 2016 and has been a fantastic addition to Jurgen Klopp's squad, as WhoScored.com demonstrated:
Mane's dynamism and versatility—he can play on either flank—would likely see him fit well into Barcelona's attack, which was severely weakened over the summer when Neymar moved to Paris Saint-Germain.
However, Mane's Liverpool contract runs to 2021, and it seems highly likely that, as with Coutinho, the Reds would refuse to sell one of their star players to Barca no matter the bid.