The Dolphins will get a conditional seventh-rounder, according to a league source.
The trade was first reported by the NFL Network and later confirmed by McCain on Twitter.
Thank you Dolphins for a wonderful 2 1/2 yrs. love Florida but GOD always has a plan. And I'm very thankful for this opportunity #whodat— Chris McCain (@DolphinEret) August 29, 2016
The Dolphins were deep at defensive end, which put McCain on the roster bubble and ultimately made him expendable. They have starters Cameron Wake and Mario Williams, who have combined for eight Pro Bowls, along with veteran backups Jason Jones and Andre Branch.
McCain (6-foot-5, 236 pounds) has pass-rush ability and can play a variety of special teams. His two signature plays in Miami were a blocked punt during his rookie season and a sack of New England Patriots quarterback Tom Brady.
The Dolphins signed McCain as an undrafted rookie in 2014. He played in 18 career games and registered seven tackles and two sacks. New Saints tight ends coach/assistant head coach Dan Campbell is familiar with McCain after serving as the Dolphins' interim head coach last year.
It's unclear if the Saints expect McCain to push third-year pro Kasim Edebali for a starting job or if they were just looking for depth and special-teams help. But the Saints have essentially been in the market for pass-rush help since back in March -- a need that became even greater after second-year defensive end Hau'oli Kikaha went down with a knee injury this summer.
New Orleans apparently decided to look outside the building for help after being disappointed with its most recent preseason results. Coach Sean Payton called the pass rush "very concerning" after Friday's preseason loss to the Pittsburgh Steelers.
"For the amount of times they threw the ball, our ability to affect the quarterback was poor," said Payton, who also hinted on Monday that the Saints would be looking outside the building for help over the next week.
"This next 10-day period, there's gonna be some good football players that shift from one team to another via a lot of different ways, be it from trade, be it waiver claims and/or free agency," Payton said.
The Saints also addressed another one of their top trouble spots Monday, signing veteran offensive lineman Khalif Barnes after a tryout.
It's unclear what his role will be in New Orleans since the 6-6, 320-pounder has played both tackle and guard. The Saints' most pressing need is at guard, but they might also be looking for a versatile swingman to provide backup at both spots.