The attacker, who turned 14 15 days ago, is a youth product of the club and signed a two-year deal.
He takes the record of youngest athlete in the United States with a professional contract from Freddy Adu. He was 153 days older than Kei is now in 2004 when he signed his first professional contract with DC United.
Adu was seen as a big promise in football, but could never live up to the high expectations.
Kei was born in Ivory Coast and grew up in Brazil. In 2017, at the age of nine, he made the crossing to San Diego with his family. In October last year, he made his debut with the Real Monarchs, the training team of Real Salt Lake, in the American second division.
At the age of thirteen, he was already the youngest debutant ever in a professional league in the United States.
