The Reds were 1-0 up against Athletic Bilbao in a pre-season friendly when Robertson went in for a challenge on Alex Berenguer by the corner flag.
There was a loud clatter as they players collided, with the Scottish star left rolling around in agony clutching his ankle.
Andy Robertson hobbled off injured on Sunday as Liverpool took on Athletic Bilbao
The left-back challenged with Bilbao’s Alex Berenguer and came off worst in the Anfield game
Robertson’s absence for the start of the season would be a massive blow to Jurgen Klopp
Naby Keita was his closest ally when the challenged happened, and the midfielder instantly leant down to check on his team-mate.
The rest of the Liverpool XI strolled over too as Robertson buried his face in the turf, later walking off slowly with his weight on two physios.
The star looked almost shell-shocked as he hobbled away, clearly in a searing pain and he passed by Klopp in the dugout en-route to the physio room.
The Liverpool boss issued an update post-match: ‘We don’t know obviously at the moment how serious it is.
Jurgen Klopp will be desperate for good news on his star left-back ahead of the season start
‘It was pretty painful, that’s why Andy went off. He got the ball on the front of his foot then twisted his ankle.
‘The pain settled already but we can’t say anything further without further assessment tomorrow. He will have a scan and then we will know more.’
Berenguer survived the challenge fine enough to score an equaliser in the second-half, tucking home Inaki Williams’ cross to leave the scores at 1-1 at full-time.
Klopp has been haunted by defensive injuries in the last 12 months, and won’t fancy a fresh one with the 2021-22 Premier League campaign less than a week away.
Liverpool’s title defence collapsed last season after long-term injuries to Virgil van Dijk and Joe Gomez in the early matches led to a nightmare selection crisis.
Robertson’s injury will be a worry for Klopp, who admitted it looked ‘pretty awful’ for the Scot
Absentees piled-up with Joel Matip and Fabinho also enduring periods on the sidelines, with Jordan Henderson and Under 23 players like Nat Phillips having to step-up at centre-back.
The Anfield side were also knocked-out of the Champions League in the quarter finals by Real Madrid, and Klopp will want all his available first-choice stars to help them get back on track this season.
They’ll start their season on Saturday with a trip to Carrow Road to play newly promoted Norwich.
Source: Daily Mail