The move comes after several months of rumors about a potential deal, with Celta confirming Pineda will have a five-year contract through June 2027.
Pineda's career has been on the rise in the last couple of years for club and country and is expected to bolster Celta's attack, playing on the wings or in a more interior midfield role.
With Cruz Azul, he was a key figure who helped them end their title drought through a Liga MX championship in the 2021 Clausura. With the Mexican national team, the 25-year-old has recently established himself as a reliable option for manager Gerardo "Tata" Martino through six World Cup qualifying appearances in 2021.
At Celta, he'll now be tasked with helping rejuvenate the Galician side that have made a very gradual and slow climb out of the bottom and into the mid-table of Spain's top flight this season.
Pineda's transfer is the first and only move so far of the winter window for a Mexican talent from Liga MX into a major European league. Liga MX has proven to be an insular transfer market that can hold onto domestic names like Pineda, and in his case, the player had to wait until he was a free agent to make the leap to Spain.
Now at Celta, Pineda will play alongside fellow El Tri teammate, defender Nestor Araujo. Celta's coach, Eduardo "Chacho" Coudet, also spent time in Liga MX through a short stint as manager of Club Tijuana in 2017.