Roberto Firmino's importance to Liverpool's forward line surpasses that of even Mohamed Salah, according to club legend John Barnes.

And the former Reds winger also believes the team's current No.9 is so good he could have won the World Cup for Brazil this summer had he started ahead of Manchester City counterpart Gabriel Jesus.

Firmino started up front last Sunday as Liverpool began their Premier League campaign by beating West Ham United 4-0 courtesy of a Sadio Mane brace and goals from Mohamed Salah and Daniel Sturridge.

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But Barnes insists none of the goalscorers that day are as vital to the Liverpool attack as a man who didn't manage to find the back of the net in his 69 minutes on the pitch.

Speaking on behalf of Bonus Code Bets, Barnes said: "Firmino, for me, is the biggest part of [the attack].

"Everybody's talking about Salah and of course Salah has been fantastic in terms of goals he's scored, but if Liverpool had a Harry Kane, a Robert Lewandowski, or a typical No.9, I don't think Salah would score those goals.

"Not only does Firmino vacate the middle for Mane and Salah to make diagonal runs to score the goals, he also plays them in - he doesn't just move out of that position for other people to play them in.

"If you look at Liverpool's midfield players, they are hardworking players, there's no [Philippe] Coutinho there.

"The creativity really comes from Firmino; the final pass, the final incisive move, comes from Firmino.

"I've said it even last year that, for me, Firmino is the most important player for Liverpool in terms of how Jurgen Klopp wants to play."

Firmino endured something of a frustrating summer with his national team in Russia, finding himself behind Jesus in the pecking order throughout despite performing impressively in his four appearances from the bench.

Brazil saw their tournament ended by a disappointing defeat to Belgium at the quarter-final stage and Barnes thinks things would have panned out differently had Tite plumped for Firmino.

He added: "Firmino is a centre-forward who drops off to bring people into play and I feel had Firmino played in the World Cup, Brazil would have won.

"I think if you look at Willian, Coutinho and Neymar behind Firmino [it's similar to] how Salah and Mane play behind Firmino.

"Gabriel Jesus [is] a good goalscorer but doesn't bring people into play, he doesn't hold the ball up, he doesn't create as much for the runners as Firmino does.

"You can see why Mane and Salah have done so well and for me more than half of it is down to the way Firmino plays with them."

Liverpool's prospects of ending their 28-year wait for the Premier League title have been talked up this summer after an investment of £170million in the playing squad.

Barnes agrees with the wider consensus that the Reds have the best chance of challenging champions Manchester City as a result – though he isn't convinced they will overhaul Pep Guardiola's team.

He continued: "I think they will be City's closest challengers.

"I still think City will win the league - I don't think they'll have as good a season this year in terms of all the points and goals and winning by that far ahead - however, I feel their closest challengers will be Liverpool.

"I don't think [Liverpool will] necessarily fall short, I just think that City are so consistent and so good and so much better than everyone else that unless they become inconsistent they will win the league.

"I think Liverpool will be more consistent than they were last year. If Liverpool were 25 points off last year and they finish six points off this year - that is a fantastic season.

"I don't think they will necessarily make up that 25-point gap. I don't think they'll fall short because to finish second, six points off Man City, is not failure as far as I'm concerned.

"That's getting closer, and then you have to work hard to get closer again. I'm very hopeful this season."