The 24-year-old made an impressive start to the new season by scoring a brace in the 4-3 win over Arsenal on Sunday, including a sublime free-kick from range, prompting the following assessment from former Anfield attacker Heskey.
"I think he's got the ability to match Messi and Ronaldo," Heskey told Omnisport.
"I think he's got just as much ability as them and we've seen it in spurts.
"We need to see it more on a constant level now. His skills are phenomenal.
"I've seen it when he was at Inter and some of the videos that you see from there in training ... wow. He's a phenomenal player.
"Those players come round only once in a lifetime really. He's a phenomenal player. That's why he's going to have teams interested in him, but he is a massively important player to Liverpool."