The Sun Sentinel's Omar Kelly reported earlier in the day an MRI on the knee showed no structural damage but that the Dolphins had yet to determine how long Tannehill could potentially be out of action.
According to Schefter and Darlington, Tannehill and the team will receive second and third opinions on his injured knee before making a decision about his status for the 2017 season.
Darlington added the decision will take several days.
A sprained left ACL and MCL ended Tannehill's 2016 campaign after 13 games. A source told Schefter and Darlington the re-injured left knee was "a ticking time bomb that was going to go off at any time" since Tannehill didn't undergo surgery to fully address the injury.
Should Tannehill be lost for the year, the Dolphins would need to sign another quarterback. Matt Moore started the final three regular-season games last year as well as Miami's Wild Card Round defeat to the Pittsburgh Steelers.
Even if the Dolphins are content to stick with Moore as their starter, rolling with Brandon Doughty and David Fales as the top two backups would be less than ideal for a team angling to get back to the postseason.
ESPN's Josina Anderson reported Thursday the Dolphins' front office had discussed possibly signing Colin Kaepernick, while Darlington reported Jay Cutler would potentially be willing to put off his broadcasting career with Fox Sports and sign with Miami if he had the opportunity to start for the team.