The 22-year-old Spaniard has been farmed out on loan to the likes of Rayo Vallecano and SD Huesca in recent years and has now been allowed to leave Anfield permanently.
Pacheco joined SD Huesca on loan back in January, scoring five goals in 19 games, but has been deemed surplus to requirements after returning to Liverpool having made just 17 first-team appearances for the club in total.
The 22-year-old Spanish forward has now signed a one-year deal with Madrid-based club Alcorcon and will wear the No. 11 shirt for his new side for the 2013-14 campaign.
Pacheco himself confirmed the transfer and insisted he will never forget his time at Anfield.
He Tweeted: "I'm proud to announce that I'm joining AD Alcorcon permanent. I wanna say massive thanks to LFC for all they gave me in 6 years.
"I will always be a red. It's been my house and I will never forget it. Thanks to all you fans for the support and hope we celebrate the premier league this season. YNWA. THANKS FOR ALL."