Firmino has scored once in four games so far this term, heading home Liverpool’s second goal in the 2-1 victory over Leicester City before the international break.
The Red’s fearsome front three have all been among the goals already this season, with last term’s Golden Boot winner Mohamed Salah scoring twice and Sadio Mane leading the way with four goals.
But Aldridge, who scored 63 goals in 104 appearances for Liverpool, believes the trio must improve ahead of Saturday’s trip to Tottenham – especially Firmino.
“The front three haven’t been at the levels that they reached last year but they’ve still been scoring goals,” Aldridge wrote in his column for the Liverpool Echo.
“For whatever reason, Roberto Firmino hasn’t been playing to his true potential yet this season so hopefully scoring for Brazil the other night will give him a big lift and he’ll come back refreshed.
“He warranted that opportunity to start for Brazil. To retain that position, he’ll need to keep his level for Liverpool at a top standard.
“He’s got a couple of goals in a couple of games now, as a striker that’s what you need. He needs to be flying and hopefully this is the start of him getting back to what he’s good at.”
Liverpool travel to Wembley to take on Spurs in a fixture the visitors lost 4-1 last season, going down to early goals from Harry Kane and Heung-Min Son and failing to recover despite a first half Salah strike.
And Aldridge says the Merseysiders can’t afford to lose battles against the Premier League’s other top sides, starting with Tottenham on Saturday.
He added: “The important thing is to not lose, especially against the top teams. Tottenham took four points off us last year and we can’t let that happen again.
“They will be up there again at the end of the season so we need to take points off them to make sure we can stay ahead of them and the likes of Manchester City and Chelsea.
“We’ve seen what they did to Manchester United, they’re no mugs. If you have an off day, they make you pay as they did against us last season.
“We’ll want to keep the unbeaten run going and if you get a draw at Tottenham, that’s not a result to turn your nose up at. But we’ll go there trying to win the game and we’re very capable of that.”
Liverpool’s game with Spurs kicks off at 12:30 on Saturday.