Liverpool captain Jordan Henderson admitted they 'weren't happy' with referee Paul Tierney during their 0-0 draw with Manchester United.
Jurgen Klopp's side were unable to break down a resolute United defence at Anfield on Sunday as they endured their third successive match without scoring a goal.
However, they could have had a great chance to take the lead right on the stroke of half-time if Tierney didn't blow his whistle five seconds early into the one added minute from the first period.
Liverpool attacker Sadio Mane is played in behind the United defence from a long through ball, but the official blew his whistle moments before the pass was played, leaving the hosts baffled by the decision.
Henderson, who played as a makeshift centre-back to cover for their injury problems, said the Liverpool players were 'frustrated' by the slightly early half-time whistle.
'We weren't happy about that as you can imagine. Strange very strange,' the England midfielder complained to Sky Sports.
'He's through on goal if he doesn't blow that. I don't know. We were frustrated at half-time, but there was plenty of time for us to score another goal but lacked quality in that last bit.'
Liverpool fans were left angered by Tierney's call, as one tweeted: 'I am genuinely fuming. There is no excuses here. 6 seconds left. You don’t blow until the allocated time is played.'
Another member of the Reds faithful shared his disgust, tweeting: 'Shocking game but Paul Tierney needs to be suspended for what he did in the first half. Blowing 6 seconds early when mane is through 1 on 1. Utter disgrace.'