Molby expects Torres and Johnson to be keen to build form and fitness ahead of this summer's World Cup, although he has some doubts as to whether Rafael Benitez will want to disrupt his side's current defensive solidity by reintroducing Johnson at right-back.
"Torres and Johnson will certainly want to be fit and flying in time for the World Cup and players of their quality will always make an impact," Molby told the Reds' official website.
"Benayoun and Torres are already back in the first-team, but the problem is when do you put Johnson back in? Obviously he's got to return to full fitness first, but what will his comeback do to the way we've been playing recently? Glen loves to attack, so his return could alter the approach of our defence.
"However, in saying that, the centre-backs will have gained a lot of confidence from our recent clean sheets, so maybe we could be at the stage where we can deploy two attacking full-backs and see how it goes. Glen could also be an option for a wide midfield role."
The Dane does expect Torres to provide a major lift after being affected by injury for so much of the current campaign.
"It's not just the fact he lifts our team and crowd, he also has an effect on the opposition," Molby added.
"The last thing any opposition want to see is Fernando Torres on the teamsheet, whether he's starting or a sub.
"He has an impact all round, but of course when you've missed the amount of matches he has with injury, you need a little bit of time to find your feet again.
"It was no surprise he came back and scored a goal on Sunday against Blackburn because that's what he does, but in terms of his overall play he'll need a little bit more time to find his best form.
"We can't afford to lose him again - we have to keep our fingers crossed he can stay fit for the remainder of the season."