Source: Dolphins release quarterback Josh Rosen

In a surprising move, the Miami Dolphins have released quarterback Josh Rosen instead of working out a trade for him, a source told ESPN's Adam Schefter on Friday.

It marks the second time a team has jettisoned Rosen over the past 17 months and puts a cap on an unsuccessful tenure in Miami. The Dolphins are admitting a mistake in trading for Rosen by giving up on him a year later. It also gives Rosen a fresh start and a rare third chance to salvage his NFL career.

Rosen, 23, is entering his third NFL season potentially with his third team. And yet, he's younger (by roughly 60 days) than Cincinnati Bengals rookie quarterback Joe Burrow. It has yet to be seen if another team is willing to take a chance on Rosen's potential, given the  Arizona Cardinals' 2018 first-round pick has a 3-13 record in the 20 games he has played.

With this release, the Dolphins have decided they are comfortable going with Ryan Fitzpatrick and Tua Tagovailoa as their only QBs throughout the 2020 season. It's likely the Dolphins will add a practice squad quarterback; Jake Rudock, who was on the Dolphins' 2019 practice squad, is an option.

Tagovailoa will be active for the Dolphins on game days some 10 months after suffering a devastating hip injury while playing for Alabama. He has looked healthy and mobile throughout training camp, but there was still some uncertainty about whether the Dolphins would feel comfortable with their 2020 first-round pick being one snap away from playing.

One of the central figures in Rosen's release was that Miami is very comfortable with Tagovailoa's development and health. He's expected to be Fitzpatrick's backup to start the season, and he could become the starter as the year goes on.

Rosen was part of a three-man quarterback competition in Dolphins training camp, but he never really gave expected starter Fitzpatrick much of a push. He also couldn't hold off Tagovailoa, who showed significant improvement this offseason.

Rosen was traded to Miami during draft weekend in April 2019 for a 2019 second-round pick and a 2020 fifth-round pick. That move hasn't worked out so far for Miami, and there wasn't a clear path for Rosen to become a starter again with the Dolphins.

It is somewhat surprising that the Dolphins decided against developing Rosen -- with his cheap $750,000 salary -- as a backup, but they clearly had seen enough of him to decide it was worth moving on from him going forward.

Rosen started three games last season for the Dolphins, completing 53% of his passes for 567 yards, one touchdown and five interceptions. He entered the lineup for Fitzpatrick ahead of a Week 3 game at Dallas, and he was benched for Fitzpatrick during the fourth quarter of a Week 6 game vs. Washington. He didn't get another opportunity to start again.

Rosen has a 22.8 Total QBR over his two seasons, last among quarterbacks to appear in at least 20 games in that span.

For Rosen, the question has not been talent. Dolphins coach Brian Flores said Rosen had the best arm of all the quarterbacks in camp, but Rosen fell behind when it came to the processing part of football -- identifying defenses pre-snap, being able to predict changing coverages and linebackers shifting, and ultimately being able to let the ball fly accurately and on time. Those are all skills Rosen has spent time working on this offseason in Miami.

"I was drafted in the first round, and I think people around the league still think I can play to a certain extent. Whenever that opportunity comes, wherever it comes, I just want to be prepared for it," Rosen said last week. "Because they're few and far between. I didn't do great with the two I already had. Not many people get third chances. I'm definitely going to seize the opportunity when it comes."

Now Rosen's career is at a crossroads, as two teams have given up on him in two years, and he's hoping he gets a third chance.