The versatile forward signed a long-term contract with Brendan Rodgers' side on Sunday and joins fellow Spanish attacker Luis Alberto and Ivory Coast international defender Kolo Toure in moving to Anfield.
|33/1||Liverpool are 33/1 with BetVictor to win the title
"I'm really happy to have come to a big club like this one. Having weighed up all my options for this window, a massive club like Liverpool was always my first choice."
The 25-year-old played across the front line and recorded 12 goals and 11 assists from 34 La Liga appearances last season as Celta Vigo finished one point above the relegation zone. Aspas also netted 23 times in the Segunda Division the previous year when the club won promotion to the Spanish top flight.
"I am a quick and skilful player. Together we will achieve a lot of success," he continued.
"I've not had the chance to talk with the manager at any length just yet but I think that good players can slot into any role and not just one set position.
"I don't know a huge amount but I've learned things from watching them on TV and of course I know all about the last two Champions League finals having seen them live on TV."