The Reds parted with the Brazil international playmaker back in the winter window of 2018.
With a big-money deal having been in the offing for some time, the funds generated from Coutinho’s sale allowed Jurgen Klopp to invest heavily in the likes of Virgil van Dijk.
New arrivals at Anfield have thrived, in what is now a record-breaking squad, but Coutinho flopped at Camp Nou.
He currently finds himself taking in a loan spell at Bayern Munich as a result and facing up to an uncertain future.
McManaman says the 27-year-old would be welcomed back to Merseyside with open arms, with Liverpool yet to find a suitable successor to the South American in a No.10 role.
The former Reds star told HorseRacing.net: “It could be that they opt to bring a certain Philippe Coutinho back to the club.
“I wouldn’t mind seeing Coutinho back. He’s a brilliant player but a lot of it is just down to economics.
“If they can bring Coutinho back for a reasonable fee and potentially sell a couple of players who aren't playing regularly, then that could work.
“There are rumours that Xherdan Shaqiri may leave at the end of the season, and Adam Lallana may want to play more often.
“If there’s space available then I’d certainly like Coutinho back, as he was a wonderful player for Liverpool. He’s that type of player that when plan A isn’t working he can change the game.
“He scored some incredible goals for Liverpool and though he’d have to win the fans over after he asked to leave, I think that most fans would recognise how good he was for Liverpool.
“He seems to have lost his way a bit at the minute, he needs a bit of TLC and an arm around him doesn’t he?
“So if he wants to come back to Liverpool and the deal was good then I’d have no qualms taking him back because he’s a lovely player.”
Coutinho took in 201 appearances for Liverpool over the course of five years, registering 54 goals and an impressive number of assists.