Liverpool have one foot in the Champions League semi-final after victory against Porto.

It was widely accepted that the Reds had been given one of the easiest quarter-final draws and their Portuguese opponents didn't trouble them too much on a comfortable evening in Anfield.

Luckily for the Liverpool supporters and their nerves, Jurgen Klopp's men wasted no time in asserting their dominance as Naby Keita opening the scoring after just five minutes.

Then, less than half an hour later and Liverpool had doubled their advantage, Roberto Firmino tapping home from a matter of yards after some impressive build-up play.

There will perhaps be some frustration that Liverpool didn't extend their margin of victory and potentially put the tie to bed, but they'll be feeling confident ahead of the trip to Portugal.

Salah's controversial tackle

However, they should probably feel a little lucky at the same time, because it seemed as though they could easily have been without Mohamed Salah for the return leg.

During the closing stages of the game, the Egyptian went unpunished for a brutal challenge on Danilo Pereira and somehow managed to avoid even a yellow card.

Whether or not the tackle was an accident remains to be seen, but in the opinion of former Premier League referee Phil Dowd, Salah should have been given his marching orders.

Dowd casts his opinion

Asking for his opinion on BT Sport, Dowd responded: "I was of the impression that they were looking at it but then didn't think it needed an official review.

"I have watched it again three or four times and my opinion is - as we are looking at it now - it endangered the safety of the opponent and should have been sanctioned with a red card.

"I heard the other way 'was it just reckless?' but the way Salah comes in, he is over the top of the ball, he catches the player and I think that should have been a red card."

"For me I thought they would have asked him to review the situation so he could have a look himself, but obviously nothing came of it."

Count yourself a lucky man, Mo.

At the end of the day, you're always in danger of dismissal when your foot lands above the ball and - potentially in injurious fashion - upon the leg of an opponent.

It was good to see that Pereira wasn't injured by the tackle and his rather subdued reaction could have played a massive role in Salah staying on the pitch afterwards.

However, the feeling of injustice could rise amongst Porto players if Salah plays a major role in the second leg and makes good of his lucky escape.

Do you think Salah should have been sent off? Have your say in the comments section below.