Chosen was elevated to the active roster from the practice squad Saturday ahead of Sunday's regular-season opener against the Jaguars.
Chosen joined the Dolphins' practice squad Aug. 29 after failing to make the 49ers' 53-man roster at the conclusion of training camp. With rookie sixth-round wideout Malik Washington (quadriceps) ruled out for Week 1, Chosen will serve as the Dolphins' fifth wide receiver behind Tyreek Hill, Jaylen Waddle, Braxton Berrios and Grant DuBose. Across nine regular-season games with Miami last season, Chosen recorded four catches (on six targets) for 126 yards and one touchdown.