A ideal start through five games is not unheard of in the Premier League as Chelsea themselves have done it four times, though both of Liverpool's previous five-for-five came in the old First Division.
After two weeks of an worldwide break both sides will be looking to maintain their early season momentum.
The Premier League Leaders enjoyed a lot of dominance from the opening minutes of the game with Firmino in the thick of things.
Jurgen Klopp described Liverpool's performance in the 2-1 win at Tottenham as their best so far in a ideal start to the season.
Liverpool continued their ideal start to the season to stay atop the Premier League after a goal in each half gave them a 2-1 victory over Tottenham Hotspur at Wembley on Saturday.
Souness said afterwards Spurs are "standing still" in the Premier League while he thinks Liverpool have their best side since they won the title in 1990.
"They never had too many clear-cut chances, which is hard to do when you come to Wembley, with Tottenham playing here".
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United were in the ascendency ten minutes into the second stanza but they were yet to create clear chances in that period. Naturally, Mourinho stroked that feather.
There is no doubt that Liverpool have moved in the right direction since that day at the old White Hart Lane with two successive top four finishes in the bag and memorable runs to three Cup finals, including the Europa and Champions League showpiece events.
"I am long enough now in this business to know no one plays a ideal season - not even [Manchester] City a year ago played a flawless season", he said. I don't know exactly at the moment, but it's something with his eye.
"For me the performance was better than the result".
"Watford is Watford, we didn't show our normal behaviour, attitudes or motivation but [against Liverpool] we competed, I have nothing to say", he added.
But when you consider that Spurs possess two of the most highly rated centre-backs in the Premier League in Jan Vertonghen and Toby Alderweireld, it doesn't stack up that they have become so vulnerable when defending crosses and set-pieces.
The next challenge is in the Champions League with a trip to Inter Milan on Tuesday when Liverpool hosts Paris Saint-Germain at the start of the group stage.
"I'm not sure if we can do it on Tuesday and then next Saturday [against Southampton] again".