Dest, 19, came to prominence with a stellar Eredivisie season in 2019-20, helping lead his side to first place in the Dutch top flight before the campaign was declared null and void due to the coronavirus pandemic.
That form had led to a fierce tussle over his future, with both Barca and the reigning German and European champions keen to add the USMNT international to their ranks.
Shhhhh ... pic.twitter.com/FcrRwES4JH— FC Barcelona (@FCBarcelona) October 1, 2020
Bayern at first appeared to have the upper hand in negotiations, with reports suggesting that the Bavarians had struck a deal with both Dest and Ajax to add the teenager to their ranks.
But to the Germans' chagrin Barcelona stole in with a €21 million (£19m/$25m) deal with Ajax, higher than the offer filed from Allianz Arena, and upon agreement of personal terms the Blaugrana have clinched the signing.
A statement from the Liga giants on their official website read: “FC Barcelona and Ajax have reached an agreement for the transfer of Sergiño Dest. The cost of the operation is 21 million euros plus a further five million in variables.
“The player will sign a contract for the next five seasons, through to the end of the 2024/25 season, with a buyout clause set at 400 million euros.
“Sergiño Dest combines many excellent qualities needed in a full back: attacking when called for, solid defensively, unruffled in possession and creative with it.
“The defender has the ability to take players on and his pace is a virtue going forward and defending. Those qualities will be on display from now on in a Barca shirt, a challenge for a fearless young full-back.”
Dest arrives at Camp Nou with the opportunity to stake his claim for the right-back spot following the exit of Nelson Semedo to Wolves.
Born in the Netherlands, he nevertheless chose to represent the United States at international level, being eligible through his Surinamese-American father.
The full-back represented the US at Under-17 and 20 level before making his senior debut against Mexico in September 2019, the first of three caps he has accrued to date.