The loan is for just one season, but Eibar have a very low purchase fee price of €2 million (£1.7m/$2.3m). However, Barcelona also included a re-purchase agreement in the deal which means they could immediately buy him back for €4m (£3.4m/$4.6m).
Sources close to the Liga clubs and the player have confirmed the Serie A side have already made contact with a view to signing Cucurella, who is under contract until June 2021, this summer.
A left-back originally, Cucurella has featured more as a winger this season, and has delivered two assists in 20 games, 16 of those starts for the Basque club.
While he has missed out on six games for Eibar, the majority of those came early in the season as he did not make his debut for the club until September 25.
The loan materialised after Cucurella featured for Barcelona during the International Champions Cup but was unable to impress manager Ernesto Valverde enough win a spot with the Liga Champions.
Instead he joined up Jose Luis Mendilibar’s side at the summer transfer deadline and has received plenty of first team action in the league as well as playing in a pair of Copa del Rey matches, where he scored his lone goal of the season.
Previously Cucurella featured for Barcelona’s B side, playing 17 times for the team in the Segunda B in 2016-17 and helping them win promotion to the Segunda, where he played 37 times last season.
His performances were enough to earn him a brief Barcelona debut, which came in last season’s Copa del Rey, making a seven-minute cameo in a 3-0 victory over Real Murcia.
Cucurella is also a Spain youth international, having previously featuring in both the UEFA Under-17 championships and the Under-19 championships for La Roja.