The Brazilian had to be stretchered off during Liverpool's 2-0 Premier League win against the Black Cats on Saturday after a clash with midfielder Didier Ndong. He was seen leaving the Reds' Melwood training base on Sunday on crutches and with his right ankle in a medical boot, per BBC Sport's Phil McNulty.
The 24-year-old—who netted five goals and provided five assists in 13 appearances prior to his injury, per WhoScored.com—has played an important role for Jurgen Klopp's side. They have made an excellent start to the 2016-17 Premier League season and are just one point behind leaders Chelsea.
A Bleacher Report panel discussed how Liverpool will now cope with Coutinho being sidelined:
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Daniel Sturridge and Divock Origi will likely be utilised as cover in the Brazil international's absence, with Roberto Firmino perhaps moving to the left flank having played most often this season in a more central position.
The likes of Georginio Wijnaldum, Adam Lallana and Sadio Mane may also find themselves shifted into new positions to make up for the loss of Coutinho.
Liverpool are better equipped than they have been in recent seasons to cover the loss of the former Inter Milan man.
Klopp will need to be creative in order to maintain his side's winning form despite Coutinho's absence, but there is enough quality in the German manager's squad to make up for the loss of their talisman.