Liverpool must have been simultaneously happy and frustrated with their goalless draw against Manchester United on Sunday night.Before the game, Jurgen Klopp surely would have been disappointed with just one point, especially considering the Reds won all but one of their Premier League games at Anfield last season.But considering how the match played out, the Reds were probably happy to leave with a point to their name and Klopp even set his expectation as low as the top four in his post-match interview.

Liverpool 0-0 Man Utd

It was the Red Devils who created the best opportunities on Merseyside with Alisson Becker called upon to make some fantastic saves from Bruno Fernandes and Paul Pogba in the second-half.

And while those crucial deflections ultimately ensured that Liverpool left with a point, they could have helped the Reds on their way to victory in a parallel universe.

Now, we're not crawling down a bizarre, hypothetical rabbit hole here, but rather referring to a strange incident mere seconds before half-time when referee Paul Tierney blew up early.

Sadio Mane incident

Liverpool players and fans alike were livid when the official called an end to the first-half five seconds ahead of time despite Thiago Alcantara playing Sadio Mane clear through on goal.

Of course, it's impossible to tell whether Mane would have gone to score past David de Gea and potentially steer Klopp's men to victory, but it was a controversial moment nonetheless.

And even with another 45 minutes' worth of water under the bridge, Reds skipper Jordan Henderson were still fuming about Tierney's premature whistling after full-time.

Jordan Henderson reacts

“Yeah, we weren’t happy about that, as you can imagine,” Henderson honestly replied, according to talkSPORT.

“Strange, very strange, you know I think he’s through on goal if he doesn’t blow, we were frustrated at half-time. There was still plenty of time for us to score the goal, but again just lacked the quality in the last bit.”

Mark Clattenburg gives his verdict

It's easy to see why Liverpool felt so aggrieved by the decision, but what's the official line from those who know best? Well, former Premier League referee Mark Clattenburg has offered his verdict.

Writing for the Daily Mail, Clattenburg penned: "He wanted play to finish in a neutral area, as is standard for referees.

"The problem was, in a split-second, Liverpool played a ball over the top and Sadio Mane was looking to get away on goal. Technically, Tierney should have waited until the minimum of one minute had been played. 

"He was helped by the fact Mane and United defender Victor Lindelof then stopped playing, so we do not know what would have happened next.

"But I would not criticise Tierney for this incident. He had a very good game, it’s just a shame we didn’t have that real intensity."

In other words, you can park your conspiracy theories at the door because Tierney had the best intentions, only to be caught out by Liverpool creating a goal-scoring opportunity for very little.

However, it's hard to escape the fact that Tierney blowed up earlier than he should have done and Kopites will have to keep their fingers crossed that it doesn't catch up them later down the line.