The 21-year-old is the No. 6-ranked prospect in baseball, according to MLB Pipeline.
Los Angeles will get an extra year of team control because it waited until after July 28 to summon Adell, who now won't be eligible to test free agency until after the 2026 campaign, notes Greg Beacham of The Associated Press.
Adell was taken 10th overall by the Angels in the 2017 MLB Draft. He slashed .289/.359/.475 with 10 home runs across three different minor-league levels in 2019.