The Reds completed a £39m swoop to sign the South American midfielder from Ligue 1 side AS Monaco last week.
Liverpool FC have brought in Fabinho to reinforce their options in the middle of the park under Jurgen Klopp.
The Reds were without England international Alex Oxlade-Chamberlain for the Champions League final.
Germany international Emre Can is being tipped to move to Serie A giants Juventus at the end of the 2017-18 season.
Liverpool FC are being linked with a swoop to sign a new goalkeeper amid talk of interest in AS Roma goalkeeper Alisson Becker.
ESPN FC pundit Moreno believes the Reds need more additions than Fabinho if the Merseyside outfit are going to challenge for the title next term.
“There are other areas where Liverpool need to pay attention to,” Moreno told ESPN FC.
“This is only step one. Fabinho is one piece. There will be a few other pieces come in.”
Liverpool FC finished in fourth place in the Premier League table last season to secure a spot in the Champions League for the second successive season.
The Reds lost 3-1 to La Liga giants Real Madrid in the Champions League final in Kiev after goals from Karim Benzema and Gareth Bale.
Liverpool FC haven’t won the Premier League title but finished in second place in 2002, 2009 and 2014.
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