Liverpool have rejected every bid from the Catalan club so far, despite the Brazilian handing in a transfer request at Anfield.
Spanish outlet Mundo Deportivo now claim Barca have turned their attention to Keita.
The 22-year-old was previously wanted by Liverpool but Jurgen Klopp had several bids turned down for the Guinea international.
Barca officials watched Keita against Schalke this weekend as they consider a move.
If the Spanish giants choose to pull the plug on their attempts to sign Coutinho, Keita could be the man they turn to.
Paris St-Germain star Angel di Maria has also been linked with a move to the Nou Camp.
Barca will have to get their business done fast with the transfer window closing this Thursday.
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Liverpool will be desperate to keep hold of Coutinho as Klopp’s side get ready for a return to the Champions League.
The Reds have started the season well and sit second in the Premier League table after two wins and a draw.
Liverpool hammered title rivals Arsenal 4-0 at Anfield yesterday.
