The Reds enjoyed a positive 2017-18 season under Jurgen Klopp despite finishing the campaign without silverware.
Liverpool FC lost 3-1 to La Liga giants Real Madrid in the Champions League final in Kiev earlier this month.
Salah was forced off in the first half with a dislocated shoulder to leave the Reds relying on Firmino and Mane.
The Senegal international scored what ultimately poroved to be a consolation goal for Jurgen Klopp’s side.
Salah scored 43 times in all competitions in his first season at the Merseyside outfit, while Mane and Firmino scored 46 times to help out the Egypt international.
However, former Spurs star Waddle believes Liverpool FC need to sign another forward to provide cover and support for the current attack.
“They need a player to support the front three,” Waddle told BBC Radio 5 Live.
Liverpool FC finished in fourth place in the Premier League table last season thanks to a 4-0 win over Brighton and Hove Albion.
The Reds have secured consecutive Champions League finishes under Klopp to ensure their continued participation in the European Cup.
Liverpool FC signed Netherlands international Virgil van Dijk moved to the Redsm from Southampton last January.
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