Salah struggled to make his mark during a short spell with Chelsea, but the 25-year-old has been in fine form for Liverpool since joining the club from Roma in last summer's transfer window.
Indeed, the attacker has scored 30 times in 36 appearances in all competitions during the 2017-18 campaign, and Molby has lavished praise on the Egyptian for his impressive first season at Anfield.
"There's nothing quite like watching a player who has that coolness about him, which a lot of people – including myself – doubted he had when he first arrived," Molby told the Liverpool Echo.
"He has kept on improving, and if you add his latest strike to his effort against Tottenham the other week, Salah is very close to becoming the complete footballer. I've always been a fan of players with composure, of which Salah has in abundance.
"That little keepy-uppy and calm finish [against Porto] where he knows the shot can't be saved, it was almost like time stood still. Sometimes it can be like that as a footballer. He would have felt in complete control of that situation, and was doing things at his own pace."
Salah has netted 22 Premier League goals this season, in addition to scoring six times in seven Champions League fixtures.