Former Manchester United captain Roy Keane has named one Liverpool player that he still has doubts over. The Reds faced their bitter rivals at Anfield in the Premier League on Sunday afternoon, with the former Republic of Ireland international on punditry duty for the fixture.

Keane was previewing the fixture before kick-off when he named Andy Robertson as a player that his former club would target as a weakness in the clash on Merseyside. The Scotland international started at left-back as Arne Slot handed the full-back his 20th start in all competitions.

However, Keane believes there are 'question marks' over Robertson's form for Liverpool over the last 18 months. The Man United legend was in the Sky Sports studio alongside former Reds striker Daniel Sturridge when he gave his opinion on Robertson.

READ MORE: Jamie Carragher shares Trent Alexander-Arnold Liverpool theory and says 'there's been a frustration'

READ MORE: Michael Owen's reaction to whether he's a 'Liverpool legend' speaks volumes

"The one player I would look at Liverpool and I have question marks over in the last year or two is Robertson," said Keane on Sky Sports. "I do think if you've got a chance to run at him, you make the most of that."

This is not the first time that Keane has been critical of Robertson during the left-back's time at Liverpool. It was during the 2022/23 season that Keane labelled the Reds star as a "big baby" following an incident during a Premier League match against Arsenal.

Keane was in the Sky Sports studio in April 2023 for their coverage of Liverpool's 2-2 draw with Arsenal. During the game there was an alleged elbow from assistant referee Constantine Hatzidakis on Robertson.

The FA investigated the incident, and no further action was taken against Hatzidakis. Keane was critical with his verdict on Robertson, though, nearly two years ago.

"I've not seen anything like it really," said Keane in April 2023. ''But Robertson... does he grab the linesman first? I'm not sure. But Robertson's complaining. He should be more worried about his defending.

"I've watched Robertson a number of times and he is a big baby. Just get on with the game and concentrate on your defending. He does grab the linesman first."