Indeed, the Reds legend - and then Liverpool captain - admits he immediately feared for the striker's Premier League status... because his physique made him look like a 15-year-old.
On page 53, during the chapter 'Changing Seasons,' Gerrard wrote: "Straightaway, as soon as I saw them [Aspas and Luis Alberto] in the dressing room, I knew they weren't going to make it in the Premier League.
"It boiled down to physique. They had the bodies of little boys - they looked about fifteen. I thought 'Jesus, how are you going to cope against John Terry, Ashley Williams and Ryan Shawcross?'"
Not for the first time, Gerrard has hit the nail on the head.
People can pretend Liverpool ruined or misused Aspas but, as so many have shown over the years - Angel Di Maria being a prime example - you need a certain physicality in the Premier League. Aspas fell well, well short of that required level.
What Liverpool, the transfer committee and Brendan Rodgers can be blamed for is buying the now 28-year-old in the first place. The best of luck to him in La Liga, with Aspas now having achieved something not many individuals in world football will ever do - single-handedly tearing apart a Barcelona defence.
Gerrard's reasoning, though, explains exactly why the Spaniard was never going to make it in the Premier League.