RTÉ analyst Kevin Doyle believes that Liverpool ‘took their foot of the gas’ in the second half of their 2-0 Champions League over Porto but added that the Reds can’t be at 100mph all the time.

Goals from Naby Keita and Roberto Firmino earned Liverpool a 2-0 win over Porto as the hosts took the upper hand in their Champions League quarter-final tie without killing off their Portuguese opponents.

There remains plenty of work to do for the Premier League leaders, who will be disappointed they were unable to gain a bigger advantage for next week's second leg.

Liverpool were below their best, particularly in the second-half when their front three of Firmino, Sadio Mane and Mo Salah failed to reach the heights they’re expected to.

However former Ireland international Doyle believes there’s nothing to worry about for Liverpool supporters and claimed that the players will have to restrain themselves at times as they challenge in both Europe and domestically.

"It’s understandable, they were 2-0 up and it seemed reasonably easy in the first half, I think they just took their foot off the gas," he said on RTÉ Soccer Social.

"It’s a long season, you would want them to keep going, make it so the tie is over but it’s understandable.

"They can’t be at it for 90 minutes every game all the time, it’s a psychological thing, when the thing is going easy and you’re creating chances you just think it’s going to happen all game, it wasn’t the case in the second half.

"They’re against a good team in Porto, it’s wasn’t a Mickey Mouse team, they won five and drew one in their group, it’s like they’re up against someone they should be beating 4-0 or 5-0.

"Listen at 2-0, they should be happy."

Richie Sadlier echoed Doyle sentiments and insisted that Liverpool are exactly where they would have wanted to be coming into this tie.

"I think they were far more impressive in the first half and I wouldn’t be overly concerned that they weren’t hitting fifth gear for 100% of the match, that’s not how football works.

"They’re 2-0 up going into the second-leg of the quarter-final, it’s very, very strong position and I think it’s because they’ve set very high standards entertainment wise as well.

"The front three when they click are a joy to watch, that wasn’t the case tonight so I think that’s why people might start to look to criticise, but for me, job well done."