The Cardinals traded Rosen to the Dolphins on Friday after drafting Heisman Trophy winner Kyler Murray.
One day after the Dolphins acquired Josh Rosen, head coach Brian Flores said the quarterback will have to earn his starting job.
"When Josh gets here, he's got to compete for any type of role that he has here. That's the case for everyone in the building," Flores said, per ESPN. "The guys who produce on the practice field and do all the things that help this team win–those are the guys who will play."
Rosen will compete with veteran Ryan Fitzpatrick, who is currently seen as Miami's starting quarterback. The Dolphins traded starter Ryan Tennehill to the Titans on March 15 and signed Fitzpatrick to a two-year, $11 million just days later.
On Thursday, the Cardinals drafted Oklahoma quarterback and Heisman Trophy winner Kyler Murray with the first overall pick. Arizona sent Rosen to Miami the next day for a second-round pick and a 2020 fifth-round pick.
Rosen, who was selected with the No. 10 pick in the 2018 draft, played in 14 games during his rookie season with the 3-13 Cardinals. He threw for 2,278 yards, 11 touchdowns and 14 interceptions. The 22-year-old completed 55.2% of his passes, registering a 26.6 QBR, which ranked last among the 33 quarterbacks who qualified. Rosen was sacked 45 times last season, which ranked seventh-most in the league.