Andy Robertson will miss the start of Liverpool's Premier League season after a scan revealed ankle ligament damage.
The Scotland left-back, 27, was helped off during Liverpool's 1-1 friendly draw with Athletic Bilbao on Sunday after going over on his right ankle shortly before half-time.
Robertson left hospital on crutches and in a protective boot on Monday.
"Scan suggests nothing too major but there's some ligament damage which will need to mend," he said on Twitter.
"I will be grafting every day so I can help the team again sooner rather than later."
Liverpool have yet to confirm the extent of the damage and recovery time.
Brazil striker Roberto Firmino scored twice, after Takumi Minamino's deflected opener, as the Reds beat Osasuna 3-1 in a friendly on Monday night.
New signing Ibrahima Konate made his Anfield bow, partnering Joe Gomez, after a £36m summer move from RB Leipzig.
Jurgen Klopp's side open their league campaign on Saturday at Norwich City and then face Burnley, Chelsea and Leeds United.
"I think we got lucky with Andy, it could have been much worse," he said.
"The footage didn't look too good but we got lucky and it will not be too long. Before the international break [in early September], after the international break, I don't know [when he will be back]."
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