Per Pro Football Talk, the Cardinals would receive Miami's 2019 second-round pick at No. 48 overall in exchange for the quarterback.
NFL Network's Mike Garafolo added Arizona could send a late-draft pick back in the deal because the Dolphins believe a one-for-one trade is "too titled" in the Cardinals' favor.
Even though trading Rosen one year into his career would be unusual, the Cardinals have undergone drastic changes since the 2018 draft. The biggest was the addition of Kyler Murray with the first overall pick in this year's draft.
Steve Wilks, who replaced Bruce Arians as head coach in January 2018, was fired after the team finished 3-13. Kliff Kingsbury was hired to get the organization back on track after three straight non-winning seasons.
Speculation about Rosen's future in the desert began as soon as Kingsbury took over because of comments the then-Texas Tech head coach made about Murray prior to a game against Oklahoma on Nov. 3.
"Kyler is a freak," Kingsbury told reporters. "I'd take him with the first pick in the draft if I could. I know he's signed up to play baseball, but he is a dominant football player, and I would take him with the first pick."
Kingsbury initially shot down any speculation the Cardinals would attempt to get rid of Rosen by calling the former UCLA star "our guy."
After Murray put to rest doubts about his size by measuring in at 5'10⅛" and 207 pounds at the NFL Scouting Combine, it seemed inevitable he would be selected by Arizona.
"In terms of Murray, people are beginning to believe almost universally he will indeed be the No. 1 pick in this draft by the Arizona Cardinals," NFL Network's Kimberly Jones reported (via NFL.com's Jeremy Bergman). "In fact, teams picking in the top 10 believe they'll have no chance of drafting Murray. He's not the biggest quarterback in the world, but he is a very big presence at this combine."
Because the Cardinals owned the top pick in this year's draft but need plenty of roster help to get back in the playoff mix, Rosen's contract, age and upside make him their most valuable trade chip.
Kingsbury has the quarterback he wants, while Rosen is in an unusual position.
Rosen could begin anew with the Dolphins after an inconsistent rookie campaign. He threw for 2,278 yards and 11 touchdowns with 14 interceptions in 14 games. He was the second-youngest starting quarterback in the NFL last season, ahead of only Sam Darnold of the New York Jets.
Miami would be a perfect landing spot. The Dolphins are in the early stages of a full-scale rebuild with Ryan Fitzpatrick penciled in as the starting quarterback, so there won't be instant pressure on Rosen to carry the franchise.
Given his age and high ceiling, the Dolphins have nothing to lose. If he hits, they will have found a franchise quarterback.
If Rosen's struggles last season turn out to be a sign of what's to come, the Dolphins will only be out a mid-second-round pick and his minimal salary for the next three years.