Barca were baffled until the 60th moment when Antoine Griezmann turned in Frenkie de Jong’s cross before De Jong headed in himself three minutes after the fact.
Messi at that point drove from his own half, traded twice with De Jong and tracked down the base corner for Barca’s third.
Messi added his second four minutes after the fact, clearing in Jordi Alba’s cross.
Triumph gives Barca their first prize under director Ronald Koeman and their first flatware since 2019.
“To win a title is significant for me,” said Koeman, whose side are third in La Liga – two focuses behind pioneers Atletico Madrid.
“Notwithstanding the progressions at the club and the youthful players, at Barca you need to consistently battle for prizes.
“We have the first and now we will battle to the last game in La Liga.”
For Athletic is was a second Copa del Rey last loss in about fourteen days after they lost to Genuine Sociedad in the deferred 2020 last on 3 April.
Messi stars on great night for Barcelona
This has been a weird season for Barcelona which started with Messi saying he needed to leave the club and has since seen a group experiencing significant change both intrigue and disappoint.
In Seville, be that as it may, they were by a long shot the better group and would have scored before however for two phenomenal recoveries from Unai Simon.
As could be, Messi was at the bleeding edge of their assaulting play and he covered the success with two brand name objectives.
His initially incorporated the spilling, vision and completing we have generally expected all through his heavenly vocation and the second was a first-time, left-footed strike into the base corner likewise seen so regularly.
The inquiry now – one presented to his partners at full-time – is whether this prize, Messi’s seventh victory in the opposition, is sufficient to persuade the Argentine to remain.
It supports Koeman’s odds of staying into the second year of his agreement, regardless of whether his side prevail in their title race with Genuine Madrid and Atletico Madrid.